Construction structure and method of secondary lining treatment of karst stratum tunnel based on casing lining

Abstract

The present invention discloses a casing-based karst stratum tunnel secondary lining regulation construction structure and method, the structure includes a grouting anchoring structure for supporting the arch wall of the tunnel section to be regulated and a reinforcement casing for reinforcing the arch wall of the tunnel section to be regulated, the reinforcement casing is arranged on the inner side of the tunnel secondary lining, and the grouting anchoring structure is arranged on the outer side of the reinforcement casing; the method includes the following steps: 1. steel arch installation; 2. grouting anchoring construction; 3. roughening treatment of the inner wall of the tunnel secondary lining; 4. arch steel structure construction; 5. concrete casing construction. The present invention has reasonable design, simple construction and good use effect, and adopts a grouting anchoring structure to integrally reinforce the outer surrounding rock of the tunnel section to be regulated, so that the outer surrounding rock of the tunnel is tightly connected to the tunnel support structure; at the same time, a reinforcement casing is arranged in the tunnel secondary lining, further effectively improving the support strength and support effect of the constructed casing, and ensuring the regulation effect of the tunnel secondary lining.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel secondary lining regulation construction, and in particular relates to a karst stratum tunnel secondary lining regulation construction structure and method based on casing lining. Background Art

[0002] With the continuous development of high-speed railways, single-hole double-track tunnels crossing complex geological conditions are becoming more and more common, and the number of tunnel disease treatments is also increasing. The tunnel vault has problems such as falling blocks on the lining surface due to concrete extrusion, hollowing out of the upper part of the secondary lining concrete, and twisting and deformation of the steel frame, which further increase the risk of collapse and seriously threaten driving safety. Karst geology is mainly the product of chemical dissolution and mechanical destruction of soluble rock formations by surface water and groundwater during runoff, recharge, infiltration and circulation. After the construction of a tunnel crossing a karst stratum (i.e., a karst stratum tunnel) is completed, there are many tunnel diseases that need to be sorted out, especially when the geology of the tunnel body through the area is complex, and the strata in the area through which the tunnel body passes have the characteristics of rich water, caves, faults, high ground stress, dangerous rock falls, and lateral pressure. It is necessary to promptly treat the tunnel secondary lining diseases that appear.

[0003] In actual treatment of tunnel secondary lining defects, the method of applying sleeve lining is usually adopted. Sleeve lining is lining, which is mainly used for the treatment of tunnel secondary lining (i.e. tunnel secondary lining) problems. When the quality of tunnel secondary lining is unqualified, sleeve lining can be applied on the original secondary lining structure surface, and then the gaps are filled with grouting. In actual construction, sleeve lining is to pour a certain thickness of concrete on the inner surface of the existing lining (specifically the tunnel secondary lining), and share the surrounding rock pressure with the existing lining. Sleeve lining can not only effectively prevent the existing lining from further cracking and deformation, but also play a waterproof role. However, when treating the secondary lining of a tunnel passing through karst strata, due to the characteristics of rich water, karst caves, faults, high ground stress, dangerous rock falls, and lateral pressure in the stratum where the tunnel body is located, only constructing concrete sleeve lining in the tunnel secondary lining cannot solve the tunnel secondary lining defects, and cannot effectively treat the hollow cracking section of the tunnel secondary lining. Moreover, there is no unified, standard and normative construction method to follow when using casing to treat secondary lining defects in karst stratum tunnels under complex geological conditions. In actual construction, there are inevitably many problems such as arbitrary construction operations, low construction efficiency and the inability to ensure the quality of the casing formed by construction. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a karst stratum tunnel secondary lining improvement construction structure based on casing lining in view of the deficiencies in the above-mentioned prior art. The structure has a reasonable design, is easy to construct and has good use effect. The grouting anchor structure is used to integrally reinforce the outer surrounding rock of the tunnel section to be improved, so that the outer surrounding rock of the tunnel is tightly connected to the tunnel support structure as a whole; at the same time, a reinforced casing lining is arranged in the tunnel secondary lining, and the arched steel frame is connected to the arched steel bar structure as a whole to form an integral force-bearing structure in the concrete casing lining, thereby further effectively improving the support strength and support effect of the constructed casing lining, and ensuring the improvement effect of the tunnel secondary lining.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a karst stratum tunnel secondary lining regulation construction structure based on casing, characterized in that: it includes a grouting anchoring structure for supporting the arch wall of the tunnel section to be regulated and a reinforcement casing for reinforcing the arch wall of the tunnel section to be regulated, the reinforcement casing is arranged on the inner side of the tunnel secondary lining of the tunnel section to be regulated, and the grouting anchoring structure is arranged on the outer side of the reinforcement casing;

[0006] The secondary tunnel lining is a full-section support structure for full-section support of the tunnel section to be rectified, and the secondary tunnel lining is a reinforced concrete lining; the secondary tunnel lining includes an arch wall secondary lining for supporting the arch wall of the tunnel section to be rectified and a tunnel invert arranged at the bottom of the tunnel section to be rectified, and the tunnel invert is located directly below the arch wall secondary lining and the two are connected as a whole; an initial tunnel support structure for initial support of the tunnel section to be rectified is arranged on the outside of the secondary tunnel lining, and the initial tunnel support structure and the secondary tunnel lining constitute the tunnel support structure of the tunnel section to be rectified; the grouting anchor structure is fastened to the reinforcement sleeve lining and the tunnel support structure as a whole;

[0007] The reinforcement sleeve comprises a concrete sleeve cast by concrete, a plurality of steel arch frames arranged in the concrete sleeve from front to back along the longitudinal extension direction of the tunnel, and an arched steel bar structure arranged in the concrete sleeve; the concrete sleeve is cast as a whole with the arch wall secondary lining arranged outside the concrete sleeve, and the cross-sectional shape of the concrete sleeve is the same as the cross-sectional shape of the arch wall secondary lining; the plurality of steel arch frames and the arched steel bar structure are cast in the concrete sleeve;

[0008] The plurality of steel arch frames are evenly arranged, and each of the steel arch frames is arranged on a tunnel cross section of the tunnel section to be rectified; the plurality of steel arch frames are supported on the inner wall of the secondary lining of the tunnel, and the structures and sizes of the plurality of steel arch frames are the same; the steel arch frame is an arch support supported in the secondary lining of the arch wall, and the cross-sectional shape of the steel arch frame is the same as the cross-sectional shape of the secondary lining of the arch wall; the spacing between the front and rear adjacent steel arch frames is d, wherein the value range of d is 0.8m to 1.2m;

[0009] The grouting anchoring structure comprises a plurality of locking foot anchor rod groups for supporting the arch feet on the left and right sides of the tunnel section to be rectified and a plurality of system anchor rod groups for supporting the arch portion of the tunnel section to be rectified, wherein the plurality of locking foot anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel, the structures of the plurality of locking foot anchor rod groups are the same and they are evenly arranged, and each of the locking foot anchor rod groups is located on a tunnel cross section of the tunnel section to be rectified; the plurality of system anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel and they are evenly arranged, and each of the system anchor rod groups is located on a tunnel cross section of the tunnel section to be rectified;

[0010] The distance between two adjacent locking foot anchor rod groups is d, and each locking foot anchor rod group is arranged on the same tunnel cross section as a steel arch frame; each locking foot anchor rod group includes two groups of symmetrically arranged locking foot anchor rods on the left and right; one group of locking foot anchor rods is arranged on the outer side of the left arch foot of the steel arch frame, and the other group of locking foot anchor rods is arranged on the outer side of the right arch foot of the steel arch frame;

[0011] Each group of locking foot anchor rods comprises a plurality of locking foot anchor rods arranged side by side on the same plane, and the plurality of locking foot anchor rods in each group of locking foot anchor rods are arranged in parallel and arranged from front to back along the extension direction of the tunnel; each locking foot anchor rod is gradually inclined downward from the inside to the outside and the angle between it and the horizontal plane is 15° to 25°, and the inner end of each locking foot anchor rod is fixed on the steel arch frame located on the inner side thereof;

[0012] The spacing between the two adjacent system anchor rod groups is 2d, and each system anchor rod group is arranged on the same tunnel cross section with a steel arch frame; each system anchor rod group includes a plurality of system anchor rods uniformly arranged on the same tunnel cross section along the circumferential direction, and each system anchor rod is arranged vertically to the inner wall of the secondary lining of the tunnel at its position; the inner end of each system anchor rod is fixed on the steel arch frame located on the inner side thereof; the system anchor rods of the two adjacent system anchor rod groups are arranged in a staggered manner;

[0013] The locking foot anchor rod and the system anchor rod are both straight anchor rods that enter the outer surrounding rock of the tunnel section that needs to be repaired after passing through the tunnel support structure. The locking foot anchor rod and the system anchor rod are both self-propelled anchor rods and both are grouting anchor rods. The bottom of the left and right sides of the arch wall secondary lining are provided with a plurality of locking foot anchor rod installation holes for the installation of locking foot anchor rods, and the arch part of the arch wall secondary lining is provided with a plurality of system anchor rod installation holes for the installation of system anchor rods. The locking foot anchor rod installation holes and the system anchor rod installation holes are both straight holes drilled from the inside of the tunnel secondary lining from the inside to the outside to the outer surrounding rock of the tunnel section that needs to be repaired.

[0014] The above-mentioned karst stratum tunnel secondary lining improvement construction structure based on casing lining is characterized in that the area where the system anchor rods are arranged in the arch part of the secondary lining of the arch wall is the system anchor rod layout area, and the central angle of the system anchor rod layout area is A, where the value range of A is 135°~145°.

[0015] The above-mentioned karst stratum tunnel secondary lining improvement construction structure based on sleeve lining is characterized in that: each of the steel arch frames is formed by bending an I-beam, the web of the I-beam is arranged vertically, one wing plate of the I-beam is an outer wing plate supported on the inner wall of the secondary lining of the arch wall, and the other wing plate of the I-beam is an inner wing plate located on the inner side of the outer wing plate; each of the steel arch frames is fixedly installed on the inner wall of the secondary lining of the arch wall through an arch frame fixing structure; each of the arch frame fixing structures includes a plurality of arch frame fixing parts, the structures and sizes of the plurality of arch frame fixing parts are the same and they are all arranged on the same tunnel cross section of the tunnel section to be improved, the plurality of arch frame fixing parts are arranged along the outer contour line of the steel arch frame, and the plurality of arch frame fixing parts constitute a wing plate fixing structure for fixing the outer wing plate;

[0016] Each of the arch frame fixing parts includes two symmetrically arranged front and rear fasteners, and the two fasteners are respectively fastened on the front and rear sides of the outer wing plate; each of the fasteners includes a fastener pressed on the outer wing plate and a fastener fixing the fastener to the tunnel support structure, the fastener is formed by bending a straight steel plate and is divided into a fastener plate pressed on the outer wing plate and a fixing plate arranged on the inner wall of the secondary lining of the arch wall, the fixing plate is located on the outside of the fastener plate, and the fastener is installed on the fixing plate; each of the fasteners is arranged vertically with the inner wall of the secondary lining of the arch wall at its position, and each of the fasteners extends from the inside to the outside of the tunnel support structure; the fastener is a chemical anchor bolt, and the fixing plate is provided with a mounting hole for the installation of the chemical anchor bolt.

[0017] The above-mentioned karst stratum tunnel secondary lining renovation construction structure based on sleeve lining is characterized in that: the arched steel bar structure includes a plurality of annular steel bar groups arranged from front to back in the tunnel section to be renovated along the longitudinal extension direction of the tunnel and a plurality of longitudinal steel bars all arranged horizontally, the lengths of the plurality of longitudinal steel bars are the same and their front ends are all arranged on the same tunnel cross section of the tunnel section to be renovated; the structures and sizes of the plurality of annular steel bar groups are the same, each of the annular steel bar groups is arranged on a tunnel cross section of the tunnel section to be renovated, the plurality of annular steel bar groups are fastened and connected as a whole by the plurality of longitudinal steel bars, and each of the longitudinal steel bars is located on the inner side of the plurality of annular steel bar groups;

[0018] Each of the steel arch frames is arranged between two adjacent annular steel bar groups, and a plurality of annular steel bar groups are arranged between two adjacent steel arch frames; each of the steel arch frames is located outside the plurality of longitudinal steel bars, and the inner wing plates of each of the steel arch frames are welded and fixed to the plurality of longitudinal steel bars as a whole;

[0019] Each of the annular steel bar groups includes a plurality of anchoring stirrups, an outer annular steel bar arranged on the inner wall of the tunnel secondary lining, and an inner annular steel bar arranged inside the outer annular steel bar; the outer annular steel bar and the inner annular steel bar in each of the annular steel bar groups are arranged on the same cross section of the tunnel section to be rectified, and both are arched steel bars arranged on the inner side of the arch wall secondary lining, and the shapes of the outer annular steel bar and the inner annular steel bar are the same as the cross-sectional shape of the arch wall secondary lining; the plurality of anchoring stirrups in each of the annular steel bar groups are arranged on the same cross section of the tunnel section to be rectified, and the plurality of anchoring stirrups are arranged along the inner contour line of the arch wall secondary lining, and each anchoring stirrup is arranged vertically to the inner wall of the arch wall secondary lining at the position where it is arranged; the plurality of anchoring stirrups in each of the annular steel bar groups are fastened and connected as a whole through the outer annular steel bar and the inner annular steel bar;

[0020] Each of the anchoring stirrups is divided into an outer anchoring section anchored in the secondary lining of the arch wall and an inner connecting section located inside the outer anchoring section, the outer end of the outer anchoring section is an anchoring head formed by bending; the inner end of the inner connecting section is a hook formed by bending, the hook is hung on the inner annular steel bar and the two are fixedly connected by spot welding; the outer end of the inner connecting section is connected to the outer annular steel bar;

[0021] The plurality of longitudinal steel bars are arranged along the inner contour line of the secondary lining of the arch wall, and each of the longitudinal steel bars is connected to the plurality of outer annular steel bars in the arch steel bar structure;

[0022] The internal connection section, longitudinal reinforcement, outer annular reinforcement and inner annular reinforcement in the arched reinforcement structure are all cast in the concrete lining.

[0023] The above-mentioned karst stratum tunnel secondary lining treatment construction structure based on sleeve lining is characterized in that: the bottoms of the left and right sides of the secondary lining of the arch wall are both provided with support grooves for supporting the arch feet of the steel arch frame, and the support grooves are installation grooves formed by chiseling away the concrete at the bottom of the secondary lining of the arch wall; the bottom surface of the support groove is a horizontal surface, and the bottom surface of the support groove is located below the upper surface of the ditch cable trough in the tunnel section to be treated;

[0024] The left and right arch feet of the arched steel bar structure are both supported on the bottom surface of one of the support grooves.

[0025] The above-mentioned karst stratum tunnel secondary lining treatment construction structure based on casing lining is characterized in that: the reinforcement casing lining also includes two left and right bottom joint steel bar groups, each of which is arranged at the bottom of one of the support grooves;

[0026] Each of the bottom joint steel bar groups includes multiple groups of joint steel bars arranged from front to back along the longitudinal extension direction of the tunnel, and each group of the joint steel bars includes two left and right joint steel bars arranged on the same tunnel cross section, and the two joint steel bars are arranged vertically; each of the joint steel bars is divided into a lower anchoring section and an upper exposed section located above the lower anchoring section with the bottom surface of the support groove as the boundary, and the lower anchoring section is anchored in the secondary lining of the tunnel; the lower parts of the two upper exposed sections in each group of the joint steel bars are connected by a horizontal connecting bar; all the joint steel bars in each of the bottom joint steel bar groups are arranged in two left and right columns, and each column of the joint steel bars includes multiple joint steel bars arranged from front to back along the longitudinal extension direction of the tunnel;

[0027] The upper exposed section and horizontal connecting bars in the bottom joint steel bar group are cast in the concrete lining.

[0028] The above-mentioned karst stratum tunnel secondary lining improvement construction structure based on casing lining is characterized in that the length of the locking foot anchor rod and the system anchor rod entering the outer surrounding rock of the tunnel section to be improved is not less than 4m.

[0029] The above-mentioned karst stratum tunnel secondary lining treatment construction structure based on casing lining is characterized in that: the excavation section of the tunnel section to be treated is greater than 100m 2 ;

[0030] The concrete casing is divided into 7 casing casting sections along the circumferential direction, and the 7 casing casting sections are arranged along the longitudinal extension direction of the tunnel; the 7 casing casting sections include a crown casting section, two symmetrically arranged upper waist casting sections, two symmetrically arranged lower waist casting sections and two symmetrically arranged side wall casting sections. The crown casting section, the upper waist casting section, the lower waist casting section and the side wall casting section are arranged from top to bottom, and the two upper waist casting sections are symmetrically connected to the left and right sides of the crown casting section, and each lower waist casting section is connected between one crown casting section and one side wall casting section; each side wall casting section is located inside the side wall of the tunnel section to be rectified, and the vertical height of the side wall casting section is 3m to 3.5m; the cross sections of the upper waist casting section, the lower waist casting section and the crown casting section are all arc-shaped;

[0031] The secondary lining of the tunnel is provided with an arched formwork for forming the concrete lining;

[0032] The arch formwork is assembled by an arch forming formwork for forming the arch casting section, two upper arch waist forming formworks symmetrically arranged on the left and right and forming the upper arch waist casting section, two lower arch waist forming formworks symmetrically arranged on the left and right and forming the lower arch waist casting section, and two side wall forming formworks symmetrically arranged on the left and right and forming the side wall casting section. The cross sections of the arch forming formwork, the upper arch waist forming formwork and the lower arch waist forming formwork are all arc-shaped; the cross section shape of the arch forming formwork is the same as the cross section shape of the inner wall of the arch casting section, and the upper arch waist forming formwork is The cross-sectional shape is the same as the cross-sectional shape of the inner wall of the upper arch waist casting section, the cross-sectional shape of the lower arch waist forming template is the same as the cross-sectional shape of the inner wall of the lower arch waist casting section, and the cross-sectional shape of the side wall forming template is the same as the cross-sectional shape of the inner wall of the side wall casting section; the two upper arch waist forming templates are symmetrically arranged below the left and right sides of the arch crown forming template, each of the lower arch waist forming templates is located between one of the upper arch waist forming templates and one of the side wall forming templates, and the bottom of each of the side wall forming templates is supported on a ditch cable trough in the tunnel section to be rectified, and the ditch cable trough is a concrete trough;

[0033] The arch crown forming formwork, the upper arch waist forming formwork, the lower arch waist forming formwork and the side wall forming formwork are all sleeve lining forming formworks; the sleeve lining forming formwork comprises a steel formwork, a plurality of formwork stiffening ribs arranged on the inner side of the steel formwork and a plurality of formwork tie rods fixing the steel formwork to the secondary lining of the arch wall, the plurality of formwork stiffening ribs are arranged in parallel and arranged from front to back along the longitudinal extension direction of the tunnel, each of the formwork stiffening ribs is arranged on a tunnel cross section of the tunnel section to be rectified, and the shape of each formwork stiffening rib is the same as the cross-sectional shape of the steel formwork at the position where it is arranged; each of the formwork tie rods is arranged perpendicularly to the inner side wall of the secondary lining of the arch wall at the position where it is arranged, the inner end of each of the formwork tie rods is anchored to the secondary lining of the arch wall, the outer end of each of the formwork tie rods extends to the inner side of the steel formwork, and the steel formwork is provided with a plurality of through holes for the formwork tie rods to extend;

[0034] The arch casting structure includes a plurality of vertical grouting pipes arranged from front to back along the longitudinal extension direction of the tunnel, the plurality of vertical grouting pipes are arranged on the same vertical plane and are located directly below the arch of the tunnel section to be renovated, and the plurality of vertical grouting pipes are evenly arranged; the upper end of each vertical grouting pipe extends above the arch forming template, and the bottom end of each vertical grouting pipe extends below the arch forming template, and a plurality of grouting holes for installing the vertical grouting pipes are opened from front to back in the middle of the arch forming template.

[0035] At the same time, the present invention also discloses a karst stratum tunnel secondary lining treatment construction method with simple steps, reasonable design, simple construction and good use effect, characterized in that the method comprises the following steps:

[0036] Step 1: installing the steel arch frame: installing multiple steel arch frames respectively from the back to the front in the tunnel section to be rectified along the longitudinal extension direction of the tunnel, and making each of the steel arch frames fixedly supported on a cross section of the tunnel section to be rectified;

[0037] The tunnel section to be regulated is a tunnel section passing through a karst stratum;

[0038] Step 2, grouting and anchoring construction: in the process of installing the multiple steel arch frames from back to front in step 1, the multiple locking foot anchor rod groups in the grouting and anchoring structure are constructed from back to front, and each locking foot anchor rod group is arranged on the outside of a steel arch frame that has been installed; the construction methods of the multiple locking foot anchor rod groups are the same;

[0039] When constructing any one of the locking foot anchor rod groups, the left and right locking foot anchor rods in the locking foot anchor rod group are constructed symmetrically;

[0040] In this step, during the process of constructing the multiple locking anchor rod groups in the grouting anchor structure from back to front, the multiple system anchor rod groups in the grouting anchor structure are constructed from back to front, and each system anchor rod group is arranged on the outside of a steel arch frame that has been installed; the construction methods of the multiple system anchor rod groups are the same;

[0041] When constructing any one of the system anchor rod groups, multiple system anchor rods in the system anchor rod group are constructed symmetrically on both sides;

[0042] After the construction of the plurality of locking foot anchor rod groups and the plurality of system anchor rod groups in the grouting anchoring structure is completed, the grouting anchoring structure is formed;

[0043] Step 3: Roughening the inner wall of the secondary lining of the tunnel: Roughening the inner wall of the secondary lining of the tunnel section to be rectified;

[0044] Step 4: constructing the arched steel bar structure: constructing the arched steel bar structure from back to front along the longitudinal extension direction of the tunnel, and fixing and connecting the constructed arched steel bar structure to the plurality of steel arch frames in step 1;

[0045] Step 5, concrete lining construction: concrete pouring construction is carried out on the concrete lining to obtain a constructed concrete lining, and the multiple steel arch frames in step 1 and the arched steel bar structure in step 4 are poured into the concrete lining.

[0046] The above method is characterized in that: when any one of the locking foot anchor rod groups is constructed in step 2, when any one of the locking foot anchor rods in each of the locking foot anchor rod groups is constructed, the following steps are included:

[0047] Step A1, drilling: using a drilling device to drill a locking foot anchor rod installation hole of the currently constructed locking foot anchor rod to obtain the constructed locking foot anchor rod installation hole;

[0048] Step A2, anchor rod installation: install the currently constructed locking foot anchor rod from the inside to the outside into the locking foot anchor rod installation hole described in step A1, and fix the outer end of the installed locking foot anchor rod to one of the steel arch frames;

[0049] Step A3, grouting: injecting cement slurry into the outer surrounding rock of the tunnel section to be rectified through the locking anchor rods described in step A2, and grouting reinforcement is performed on the outer surrounding rock of the tunnel section to be rectified at the location of the locking anchor rods;

[0050] Step A4, plugging the hole opening: after the grouting in step A3 is completed, the hole opening of the locking foot anchor rod installation hole is plugged to complete the construction process of the currently constructed locking foot anchor rod;

[0051] When any one of the system anchor rod groups is constructed in step 2, when any one of the system anchor rods in each of the system anchor rod groups is constructed, the following steps are included:

[0052] Step B1, drilling: using a drilling device to drill the system anchor bolt installation hole of the currently constructed system anchor bolt to obtain the constructed system anchor bolt installation hole;

[0053] Step B2, anchor rod installation: install the currently constructed system anchor rod from the inside to the outside into the system anchor rod installation hole described in step B1, and fix the outer end of the installed system anchor rod to one of the steel arch frames;

[0054] Step B3, hole opening plugging: after the system anchor rod is installed in step B2, the hole opening of the system anchor rod installation hole where the system anchor rod is located is plugged to obtain a hole opening plugging structure; at the same time, an exhaust pipe is installed in the hole opening plugging structure, the outer end of the exhaust pipe extends into the system anchor rod installation hole, and the inner end of the exhaust pipe extends to the outside of the hole opening plugging structure;

[0055] Step B4, grouting: inject cement slurry into the outer surrounding rock of the tunnel section to be rectified through the system anchor rods described in step B3, and perform grouting reinforcement on the outer surrounding rock of the tunnel section to be rectified at the location of the system anchor rods.

[0056] Compared with the prior art, the present invention has the following advantages:

[0057] 1. The structural design is reasonable and the construction is simple, with low construction cost.

[0058] 2. The grouting anchoring structure used is reasonably designed, easy to construct and has good anchoring effect. Multiple locking anchor groups and multiple system anchor groups are used to reinforce the tunnel section that needs to be rectified as a whole. The locking anchor and system anchor are both self-propelled anchors and both are grouting anchors. They can grout and reinforce the surrounding rock around the tunnel section that needs to be rectified, and make the surrounding rock outside the tunnel and the tunnel support structure tightly connected as one, which can effectively tidy up the secondary lining of the tunnel passing through the karst stratum.

[0059] 3. Use multiple locking anchor rods arranged from front to back to reinforce the arch feet on both sides of the tunnel section that needs to be rectified. The construction is simple and can further improve the stability of the existing tunnel support structure. At the same time, the locking anchor rods use self-propelled grouting anchor rods to effectively grout and reinforce the surrounding rock of the arch feet on both sides of the tunnel section that needs to be rectified, solving the problem of tunnel secondary lining diseases from the root, not just reinforcing the inside of the tunnel secondary lining through the sleeve lining, which can completely solve the tunnel secondary lining treatment problem. In addition, the locking anchor rods are connected to the steel arch frame as a whole, further improving the overall stability of the support structure. In addition, each group of locking anchor rods uses multiple locking anchor rods to further improve the anchoring effect and ensure the reinforcement effect of the arch feet on both sides of the tunnel section that needs to be rectified.

[0060] 4. Use multiple system anchor groups arranged from front to back to support the entire arch and upper part of the side wall of the tunnel that needs to be repaired. The construction is simple and the use effect is good. It can effectively improve the overall stability and reliability of the tunnel and ensure construction safety. In addition, the system anchor adopts self-propelled grouting anchor, which can carry out overall grouting reinforcement on the outer surrounding rock of the tunnel arch and upper part of the side wall, solving the problem of tunnel secondary lining disease from the root, instead of only reinforcing the inside of the tunnel secondary lining through lining, which can completely solve the problem of tunnel secondary lining treatment.

[0061] 5. The adopted reinforcement sleeve structure has reasonable design, simple construction and low construction cost.

[0062] 6. The fasteners used have a simple structure, reasonable design, easy processing and manufacturing, and low investment cost. Each fastener includes a fastener pressed on the outer wing plate and a fastener fixing the fastener on the tunnel support structure.

[0063] 7. The fasteners used are easy to install and have good fixing effects. It is only necessary to press the buckle plate in the fastener onto the outer wing plate of the fixed steel arch frame, and then fix the fixing plate in the fastener with fasteners. This saves labor and time, and fixes firmly. At the same time, the fastener and the outer wing plate of the fixed steel arch frame are fixed by buckling and pressing. Not only is the fixation simple and reliable, but it can also effectively avoid the inconvenience of fixing the anchor steel bar to the steel arch frame, the inevitable damage to the structure of the steel arch frame during and after the fixing, and the impact on the supporting strength of the steel arch frame.

[0064] 8. The steel arch frame is fixed by arch frame fixings, and each arch frame fixing piece adopts a buckling fixing method in which two symmetrically arranged fasteners are used to fix the outer wing plate of the steel arch frame. This fixing method does not require opening fixing holes on the steel arch frame or welding with steel bars, so it will not effectively avoid any damage to the steel arch frame. In addition, there is no direct fixing relationship between the steel arch frame and the arch frame fixing piece, which makes it easy to adjust the position of the fixed steel arch frame, and can easily and quickly install the steel arch frame accurately, ensuring that each steel arch frame is accurately installed in place and each steel arch frame is located on a cross section of the tunnel section to be rectified.

[0065] 9. The steel arch frame is easy to install and has good use effect. The outer wing plate of the steel arch frame is fixed by the arch frame fixing parts composed of two symmetrically arranged front and rear fasteners. The fixing process of the steel arch frame can be completed simply and quickly, and the installation quality of the fixed steel arch frame can be ensured. It is economical and practical.

[0066] 10. The adopted arched steel bar structure is reasonably designed, easy to install and has good use effect. The arched steel bar structure in the lining is divided into multiple annular steel bar groups and multiple longitudinal steel bars arranged from front to back. Each annular steel bar group includes multiple anchor stirrups arranged on the same tunnel cross section, an outer annular steel bar arranged on the inner wall of the tunnel secondary lining and an inner annular steel bar arranged on the inner side of the outer annular steel bar. The constructed lining and the tunnel secondary lining can be fastened together, and the connection strength between the constructed lining and the tunnel secondary lining can be effectively improved to ensure the lining support effect.

[0067] 11. While setting up the arched steel structure in the concrete casing, bottom joint steel bar groups are set on the arch feet on both sides of the arched steel structure to further improve the connection strength and connection quality between the constructed casing and the secondary lining of the tunnel, and the actual installation is simple.

[0068] 12. The adopted reinforcement sleeve is easy to construct and has good use effect. The arched steel frame and arched steel bar structure are set in the concrete sleeve, which can effectively improve the connection strength between the sleeve and the secondary lining of the tunnel. The arched steel frame and the arched steel bar structure are connected as a whole to form an integral force-bearing structure in the concrete sleeve, which further effectively improves the support strength and support effect of the constructed sleeve, and ensures the improvement effect of the secondary lining of the tunnel.

[0069] 13. The sleeve lining forming formwork used has a simple structure, reasonable design, easy fixation and good use effect. It can be easily and quickly fixed on the secondary lining of the arch wall and can ensure the forming quality of the concrete sleeve lining casting section.

[0070] 14. The concrete casing structure is reasonably divided, the construction is simple and the use effect is good. The concrete casing is divided into 7 casing casting sections along the circumferential direction. The 7 casing casting sections are reasonably divided, which can effectively simplify the casing concrete casting construction process and ensure the casting quality. In addition, 7 casing forming templates are assembled to form an arch template for forming the concrete casing, and the concrete casing is cast in sections from bottom to top through the arch template, which can effectively, simply and quickly complete the concrete casting process of the casing in the tunnel secondary lining, and ensure the molding quality of the concrete casing; at the same time, the arch casting structure is used to cast the arch casting section of the concrete casing, ensuring the concrete density and molding quality of the arch casting section, which can effectively prevent the existence of a cavity between the concrete casing and the existing tunnel secondary lining.

[0071] 15. The construction is simple, the construction efficiency is high and the use effect is good. The grouting anchor structure is combined with the reinforcement sleeve to carry out the tunnel secondary lining. On the one hand, the grouting anchor structure is used to integrally reinforce the outer surrounding rock of the tunnel section to be rectified, so that the outer surrounding rock of the tunnel and the tunnel support structure are tightly connected as one; on the other hand, the reinforcement sleeve is arranged in the tunnel secondary lining, and the arched steel frame and the arched steel bar structure are connected as one to form an integral force-bearing structure in the concrete sleeve, which further effectively improves the support strength and support effect of the constructed sleeve, ensures the rectification effect of the tunnel secondary lining, and conducts a second comprehensive rectification of the tunnel from both sides of the tunnel, which can effectively ensure the rectification effect of the tunnel secondary lining.

[0072] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a schematic diagram of the cross-sectional structure of the tunnel secondary lining improvement construction structure of the present invention.

[0074] Figure 2 It is a schematic diagram of the layout position of the grouting anchoring structure and the steel frame of the present invention.

[0075] Figure 3 It is a schematic diagram of the internal structure of the reinforcement sleeve of the present invention.

[0076] Figure 4 It is a schematic diagram of the longitudinal structure of the multi-frame steel arch frame of the present invention.

[0077] Figure 5 It is a schematic diagram of the vertical layout position of the steel arch frame of the present invention.

[0078] Figure 6 This is a reference diagram of the use status of the fastening member of the present invention.

[0079] Figure 7 It is a schematic diagram of the planar structure of the fastener of the present invention.

[0080] Figure 8 It is a structural schematic diagram of the steel arch frame of the present invention.

[0081] Fig. 9 It is a structural schematic diagram of the support groove of the present invention.

[0082] Fig.10 It is a schematic diagram of the connection state of the longitudinal connecting steel bars between two adjacent front and rear steel arch frames of the present invention.

[0083] Fig.11 It is a schematic diagram of the layout position of the concrete lining of the present invention.

[0084] Fig.12 It is a schematic diagram of the layout position of the arched steel bar structure of the present invention.

[0085] Fig.13 It is a structural schematic diagram of the arched steel bar structure of the present invention.

[0086] Fig.14 It is a schematic diagram of the connection state of the anchor stirrups and the longitudinal steel bars on the secondary lining of the tunnel of the present invention.

[0087] Fig.15 It is a schematic structural diagram of the anchor stirrup of the present invention.

[0088] Fig.16 It is a schematic diagram of the layout position of the bottom joint steel bar group of the present invention.

[0089] Fig.17 It is a schematic diagram of the structure of each group of jointed steel bars of the present invention.

[0090] Fig.18 It is a schematic diagram of the planar layout position of the jointed steel bars on the support groove of the present invention.

[0091] Fig.19 This is a reference diagram of the use status of the arch template of the present invention.

[0092] Fig. 20 It is a structural schematic diagram of the concrete lining of the present invention.

[0093] Fig.21 It is a structural schematic diagram of the arch forming template of the present invention.

[0094] Fig. 22 It is a structural schematic diagram of the upper arch waist forming template of the present invention.

[0095] Fig.23 It is a structural schematic diagram of the lower arch waist forming template of the present invention.

[0096] Fig.24 It is a schematic structural diagram of the side wall forming template of the present invention.

[0097] Fig.25 It is a schematic diagram of the installation position of the vertical grouting pipe of the present invention.

[0098] Fig.26 The figure is a schematic diagram of the layout positions of the upper chiseled groove and the lower chiseled groove of the present invention.

[0099] Fig. 27 The figure is a flowchart of the method of the present invention.

[0100] Description of reference numerals:

[0101] 1—Secondary lining of the tunnel; 2—Tunnel section to be rectified; 3-1—Longitudinal reinforcement;

[0102] 3-2—outer ring reinforcement; 3-3—inner ring reinforcement; 3-4—anchor stirrups;

[0103] 3-41—hook; 3-42—anchor head; 3-5—joint steel bar;

[0104] 3-6—Horizontal connecting reinforcement; 5—Tunnel initial support structure; 6—Support groove;

[0105] 7—water ditch and cable trough; 8—concrete lining; 8-1—vault casting section;

[0106] 8-2—Upper arch waist casting section; 8-3—Lower arch waist casting section; 8-4—Side wall casting section;

[0107] 9—system anchor rod; 9-1—vault forming template;

[0108] 9-2—Upper arch waist forming template;

[0109] 9-3—lower arch waist forming formwork; 9-4—side wall forming formwork;

[0110] 10—Steel formwork; 11—Formwork stiffening ribs; 12—Formwork tie rods;

[0111] 13—limiting piece; 14—backing plate; 15—vertical grouting pipe;

[0112] 16—lower chiseled groove; 17—upper chiseled groove; 18—longitudinal reinforcement plate;

[0113] 19—cavity to be filled; 20—fastener; 20-1—fastener;

[0114] 20-2—Fasteners; 21—Longitudinal connecting steel bars; 22—Lock anchor rods;

[0115] 23—steel arch frame; 23-1—outer wing plate; 23-2—inner wing plate;

[0116] 24—Reinforcement bushing; DETAILED DESCRIPTION

[0117] like Figure 1 A karst stratum tunnel secondary lining regulation construction structure based on casing is shown, comprising a grouting anchoring structure for supporting the arch wall of the tunnel section 2 to be regulated and a reinforcement casing 24 for reinforcing the arch wall of the tunnel section 2 to be regulated, wherein the reinforcement casing 24 is arranged inside the tunnel secondary lining 1 of the tunnel section 2 to be regulated, and the grouting anchoring structure is arranged outside the reinforcement casing 24;

[0118] The tunnel secondary lining 1 is a full-section support structure for full-section support of the tunnel section 2 to be rectified, and the tunnel secondary lining 1 is a reinforced concrete lining; the tunnel secondary lining 1 includes an arch wall secondary lining for supporting the arch wall of the tunnel section 2 to be rectified and a tunnel invert arranged at the bottom of the tunnel section 2 to be rectified, and the tunnel invert is located directly below the arch wall secondary lining and the two are connected as a whole; a tunnel initial support structure 5 for initial support of the tunnel section 2 to be rectified is arranged on the outside of the tunnel secondary lining 1, and the tunnel initial support structure 5 and the tunnel secondary lining 1 constitute the tunnel support structure of the tunnel section 2 to be rectified; the grouting anchor structure is fastened to the reinforcement sleeve 24 and the tunnel support structure as a whole;

[0119] Combination Figure 5 , Fig.11 The reinforcement sleeve 24 includes a concrete sleeve 8 cast by concrete, a plurality of steel arch frames 23 arranged from front to back in the concrete sleeve 8 along the longitudinal extension direction of the tunnel, and an arched steel bar structure arranged in the concrete sleeve 8; the concrete sleeve 8 is cast as a whole with the arch wall secondary lining arranged outside the concrete sleeve 8, and the cross-sectional shape of the concrete sleeve 8 is the same as the cross-sectional shape of the arch wall secondary lining; the plurality of steel arch frames 23 and the arched steel bar structure are cast in the concrete sleeve 8;

[0120] Combination Figure 4 , multiple steel arch frames 23 are evenly arranged, and each of the steel arch frames 23 is arranged on a tunnel cross section of the tunnel section 2 to be rectified; multiple steel arch frames 23 are supported on the inner wall of the tunnel secondary lining 1, and the structures and sizes of multiple steel arch frames 23 are the same; the steel arch frames 23 are arched brackets supported in the secondary lining of the arch wall, and the cross-sectional shape of the steel arch frames 23 is the same as the cross-sectional shape of the secondary lining of the arch wall; the spacing between the front and rear adjacent steel arch frames 23 is d, where the value range of d is 0.8m~1.2m;

[0121] Combination Figure 2 The grouting anchoring structure includes a plurality of locking foot anchor rod groups for supporting the arch feet on the left and right sides of the tunnel section 2 to be rectified and a plurality of system anchor rod groups for supporting the arch portion of the tunnel section 2 to be rectified. The plurality of locking foot anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel. The structures of the plurality of locking foot anchor rod groups are the same and they are evenly arranged. Each of the locking foot anchor rod groups is located on a tunnel cross section of the tunnel section 2 to be rectified. The plurality of system anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel and they are evenly arranged. Each of the system anchor rod groups is located on a tunnel cross section of the tunnel section 2 to be rectified.

[0122] The distance between two adjacent locking foot anchor rod groups is d, and each locking foot anchor rod group is arranged on the same tunnel cross section with a steel arch frame 23; each locking foot anchor rod group includes two groups of symmetrically arranged locking foot anchor rods 22 on the left and right; one group of locking foot anchor rods 22 is arranged on the outer side of the left arch foot of the steel arch frame 23, and the other group of locking foot anchor rods 22 is arranged on the outer side of the right arch foot of the steel arch frame 23;

[0123] Each group of the locking foot anchor rods 22 includes a plurality of locking foot anchor rods 22 arranged side by side on the same plane, and the plurality of locking foot anchor rods 22 in each group of the locking foot anchor rods 22 are arranged in parallel and arranged from front to back along the extension direction of the tunnel; each of the locking foot anchor rods 22 is gradually inclined downward from the inside to the outside and the angle between it and the horizontal plane is 15° to 25°, and the inner end of each of the locking foot anchor rods 22 is fixed to the steel arch frame 23 located on the inner side thereof;

[0124] The spacing between the two adjacent system anchor rod groups is 2d, and each system anchor rod group is arranged on the same tunnel cross section with a steel arch frame 23; each system anchor rod group includes a plurality of system anchor rods 9 uniformly arranged on the same tunnel cross section along the circumferential direction, and each system anchor rod 9 is arranged vertically to the inner wall of the secondary lining 1 of the tunnel at its position; the inner end of each system anchor rod 9 is fixed on the steel arch frame 23 located on the inner side thereof; the system anchor rods 9 of the two adjacent system anchor rod groups are arranged in a staggered manner;

[0125] The locking foot anchor rod 22 and the system anchor rod 9 are both straight anchor rods that enter the outer surrounding rock of the tunnel section 2 that needs to be renovated after passing through the tunnel support structure. The locking foot anchor rod 22 and the system anchor rod 9 are both self-propelled anchor rods and both are grouting anchor rods. The bottom of the left and right sides of the arch wall secondary lining are provided with a plurality of locking foot anchor rod installation holes for installing the locking foot anchor rod 22, and the arch part of the arch wall secondary lining is provided with a plurality of system anchor rod installation holes for installing the system anchor rod 9. The locking foot anchor rod installation holes and the system anchor rod installation holes are both straight holes drilled from the inside of the tunnel secondary lining 1 from the inside to the outside into the outer surrounding rock of the tunnel section 2 that needs to be renovated.

[0126] The arch foot of the tunnel section 2 to be rectified refers to the arch line of the tunnel section 2 to be rectified. The steel arch frame 23 is a steel arch frame or a grid arch frame.

[0127] The excavation section of the tunnel section 2 to be rectified is greater than 100m 2 In addition, the tunnel section 2 to be rectified is a tunnel section where defects exist on the tunnel secondary lining 1 and need to be rectified. In this embodiment, the excavation width of the tunnel section 2 to be rectified is 15m to 16m, and the excavation height of the tunnel section 2 to be rectified is 12.5m to 13.5m.

[0128] The thickness of the reinforcement sleeve 24 is 30 cm to 40 cm. In this embodiment, the thickness of the reinforcement sleeve 24 is 35 cm. During actual construction, the thickness of the reinforcement sleeve 24 can be adjusted accordingly according to specific needs.

[0129] like Figure 2 As shown, the area where the system anchor rod 9 is arranged in the arch part of the secondary lining of the arch wall is the system anchor rod arrangement area, and the central angle of the system anchor rod arrangement area is A, wherein the value range of A is 135°~145°. In this embodiment, A=140°. During actual construction, the value of A can be adjusted accordingly according to specific needs.

[0130] To further ensure the anchoring effect, the length of the locking foot anchor rod 22 and the system anchor rod 9 entering the surrounding rock outside the tunnel section 2 to be rectified is not less than 4m.

[0131] In this embodiment, the locking foot anchor rod 22 and the system anchor rod 9 are connected to the steel arch frame 23 by welding.

[0132] like Fig. 9 As shown, the bottom of the left and right sides of the secondary lining of the arch wall are provided with support grooves 6 for supporting the arch feet of the steel arch frame 23, and the support grooves 6 are installation grooves formed by chiseling away the concrete at the bottom of the secondary lining of the arch wall; the bottom surface of the support grooves 6 is a horizontal surface, and the bottom surface of the support grooves 6 is located below the upper surface of the ditch cable trough 7 in the tunnel section 2 to be rectified;

[0133] The locking foot anchor rod installation hole is a straight hole drilled from the inside to the outside of the support groove 6 to the surrounding rock outside the tunnel section 2 to be rectified.

[0134] The vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 is not less than 5 cm. In this embodiment, the vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 is 5 cm. During actual construction, the vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 can be adjusted accordingly according to specific needs.

[0135] The structures and sizes of all the locking foot anchor rods 22 in the plurality of locking foot anchor rod groups are the same, and the structures and sizes of all the locking foot anchor rods 22 in the plurality of system anchor rod groups are the same; the diameters of the locking foot anchor rods 22 and the system anchor rods 9 are both φ25mm to φ36mm. The circumferential spacing between two adjacent system anchor rods 9 in each system anchor rod group is 1.2m to 1.8m.

[0136] In this embodiment, the diameters of the locking foot anchor rod 22 and the system anchor rod 9 are both φ32 mm, and the circumferential spacing between two adjacent system anchor rods 9 in each system anchor rod group is 1.5 m. During actual construction, the diameters of the locking foot anchor rod 22 and the system anchor rod 9 and the circumferential spacing between two adjacent system anchor rods 9 in each system anchor rod group can be adjusted accordingly according to specific needs.

[0137] In this embodiment, d=1m.

[0138] Correspondingly, the spacing between two adjacent front and rear steel arch frames 23 is 1m, the spacing between two adjacent front and rear locking foot anchor rod groups is 1m, and the spacing between two adjacent front and rear system anchor rod groups is 2m.

[0139] When the locking foot anchor rod 22 and the system anchor rod 9 are actually constructed, a pneumatic gun is first used to drill holes, and then the pneumatic gun is used to drill into the anchor rod after the hole is formed to complete the installation of the anchor rod. For the convenience of connection, the locking foot anchor rod 22 and the system anchor rod 9 are welded and fixed to the steel arch frame 23 by connecting steel bars. The grouting liquid used by the locking foot anchor rod 22 and the system anchor rod 9 is cement slurry, and ordinary cement slurry can be used. In this embodiment, the cement slurry is pure cement slurry.

[0140] Combination Figure 8 Each of the steel arch frames 23 is formed by bending an I-beam, the web of the I-beam is arranged vertically, one wing plate of the I-beam is an outer wing plate 23-1 supported on the inner wall of the secondary lining of the arch wall, and the other wing plate of the I-beam is an inner wing plate 23-2 located on the inner side of the outer wing plate 23-1; each of the steel arch frames 23 is fixedly installed on the inner wall of the secondary lining of the arch wall through an arch frame fixing structure; each of the arch frame fixing structures includes a plurality of arch frame fixing parts, the structures and sizes of the plurality of arch frame fixing parts are the same and they are all arranged on the same tunnel cross section of the tunnel section 2 to be rectified, the plurality of arch frame fixing parts are arranged along the outer contour line of the steel arch frame 23, and the plurality of arch frame fixing parts constitute a wing plate fixing structure for fixing the outer wing plate 23-1;

[0141] Combination Figure 6 and Figure 7Each of the arch frame fixing parts includes two symmetrically arranged fasteners 20 at the front and rear sides, and the two fasteners 20 are respectively fastened on the front and rear sides of the outer wing plate 23-1; each of the fasteners 20 includes a fastener 20-1 fastened on the outer wing plate 23-1 and a fastener 20-2 fixing the fastener 20-1 to the tunnel support structure, the fastener 20-1 is formed by bending a straight steel plate and is divided into a fastener plate fastened on the outer wing plate 23-1 and a fixing plate arranged on the inner wall of the secondary lining of the arch wall, the fixing plate is located on the outside of the fastener plate, and the fastener 20-2 is installed on the fixing plate; each of the fasteners 20-2 is arranged vertically with the inner wall of the secondary lining of the arch wall at its position, and each of the fasteners 20-2 extends from the inside to the outside of the tunnel support structure; the fastener 20-2 is a chemical anchor bolt, and the fixing plate is provided with a mounting hole for the installation of the chemical anchor bolt.

[0142] like Fig.12 , Fig.13 and Fig.14 As shown, the arched steel bar structure includes a plurality of annular steel bar groups arranged from front to back in the tunnel section 2 to be rectified along the longitudinal extension direction of the tunnel and a plurality of longitudinal steel bars 3-1 arranged horizontally, the lengths of the plurality of longitudinal steel bars 3-1 are the same and their front ends are arranged on the same tunnel cross section of the tunnel section 2 to be rectified; the structures and sizes of the plurality of annular steel bar groups are the same, each of the annular steel bar groups is arranged on a tunnel cross section of the tunnel section 2 to be rectified, the plurality of annular steel bar groups are fastened together by the plurality of longitudinal steel bars 3-1, and each of the longitudinal steel bars 3-1 is located on the inner side of the plurality of annular steel bar groups;

[0143] Each of the steel arch frames 23 is arranged between two adjacent annular steel bar groups, and a plurality of annular steel bar groups are arranged between two adjacent steel arch frames 23; each of the steel arch frames 23 is located outside the plurality of longitudinal steel bars 3-1, and the inner wing plates 23-2 of each of the steel arch frames 23 are welded and fixed to the plurality of longitudinal steel bars 3-1 as a whole;

[0144] Each of the annular steel bar groups includes a plurality of anchor stirrups 3-4, an outer annular steel bar 3-2 arranged on the inner wall of the tunnel secondary lining 1, and an inner annular steel bar 3-3 arranged inside the outer annular steel bar 3-2; the outer annular steel bar 3-2 and the inner annular steel bar 3-3 in each of the annular steel bar groups are arranged on the same cross section of the tunnel section 2 to be rectified and both are arched steel bars arranged inside the secondary lining of the arch wall, and the shapes of the outer annular steel bar 3-2 and the inner annular steel bar 3-3 are consistent with the requirements of the tunnel section 2 to be rectified. The cross-sectional shapes of the secondary lining of the arch wall are the same; the multiple anchoring stirrups 3-4 in each of the annular steel bar groups are arranged on the same cross-section of the tunnel section 2 to be rectified, and the multiple anchoring stirrups 3-4 are arranged along the inner contour line of the secondary lining of the arch wall, and each of the anchoring stirrups 3-4 is arranged vertically to the inner wall of the secondary lining of the arch wall at the arranged position; the multiple anchoring stirrups 3-4 in each of the annular steel bar groups are fastened and connected as a whole through the outer annular steel bar 3-2 and the inner annular steel bar 3-3;

[0145] like Fig.15 As shown, each of the anchoring stirrups 3-4 is divided into an outer anchoring section anchored in the secondary lining of the arch wall and an inner connecting section located inside the outer anchoring section, the outer end of the outer anchoring section is an anchoring head 3-42 formed after bending; the inner end of the inner connecting section is a hook 3-41 formed after bending, the hook 3-41 is hung on the inner annular steel bar 3-3 and the two are fixedly connected by spot welding; the outer end of the inner connecting section is connected to the outer annular steel bar 3-2;

[0146] The plurality of longitudinal steel bars 3-1 are arranged along the inner contour line of the secondary lining of the arch wall, and each of the longitudinal steel bars 3-1 is connected to the plurality of outer annular steel bars 3-2 in the arch steel bar structure;

[0147] The inner connection section, the longitudinal reinforcement 3 - 1 , the outer annular reinforcement 3 - 2 and the inner annular reinforcement 3 - 3 in the arched reinforcement structure are all cast in the concrete lining 8 .

[0148] In this embodiment, the left and right arch feet of the arched steel bar structure are both supported on the bottom surface of one of the support grooves 6 .

[0149] like Figure 6 and Figure 7 As shown, each of the fasteners 20 includes one fastener 20-2, and the fastener 20-2 is fixed to the middle of the fixing plate. The actual processing is simple and the fixing is reliable.

[0150] In this embodiment, the plurality of arch fixing members in the arch fixing structure are evenly arranged.

[0151] The circumferential spacing between two adjacent arch fixing members in the arch fixing structure is 0.8m to 1.2m. In this embodiment, the circumferential spacing between two adjacent arch fixing members in the arch fixing structure is 1m. During actual installation, the circumferential spacing between two adjacent arch fixing members in the arch fixing structure can be adjusted accordingly according to specific needs.

[0152] like Figure 7 As shown, in this embodiment, the straight steel plate is a rectangular steel plate.

[0153] For a secure fixation, the front-to-back length of the gusset plate is 13 cm to 15 cm, and the width of the gusset plate is 10 cm to 15 cm. The front-to-back length of the fixing plate is 9 cm to 11 cm.

[0154] In this embodiment, the front-to-back length of the gusset plate is recorded as L, and L=14 cm, the front-to-back length of the fixed plate is recorded as L1, and L1=10 cm, and the width of the gusset plate is recorded as D, and D=12 cm. In actual processing, the values ​​of L, L1 and D can be adjusted accordingly according to specific needs.

[0155] like Figure 4 As shown, all the arch frame fixing parts on the multiple steel arch frames 23 are arranged in multiple rows, and each row of the arch frame fixing parts includes multiple ones arranged from front to back along the longitudinal extension direction of the tunnel.

[0156] During actual construction, the spacing between two adjacent front and rear steel arch frames 23 is 0.8m to 1.2m. In this embodiment, the spacing between two adjacent front and rear steel arch frames 23 is 1m.

[0157] In order to improve the integrity and support effect of the constructed lining, Fig.10 As shown, the outer wing plates 23-1 of the two adjacent front and rear steel arch frames 23 are connected by multiple longitudinal connecting steel bars 21. The multiple longitudinal connecting steel bars 21 are arranged horizontally and are arranged on the same tunnel cross section of the tunnel section 2 to be rectified. The multiple longitudinal connecting steel bars 21 are arranged along the outer contour line of the steel arch frame 23; the front and rear ends of each longitudinal connecting steel bar 21 are welded and fixed to the inner wall of one of the outer wing plates 23-1. When actually fixing, each longitudinal connecting steel bar 21 is located between two adjacent arch frame fixing parts in the arch frame fixing structure.

[0158] For ease of processing and manufacturing, in this embodiment, each of the steel arch frames 23 is formed by splicing together a plurality of I-beam segments arranged on the same vertical plane.

[0159] During actual construction, the left and right arch feet of the arched steel bar structure are both supported on the bottom surface of a support groove 6, specifically, the left and right arch feet of the outer annular steel bar 3-2 and the inner annular steel bar 3-3 are both supported on the bottom surface of a support groove 6.

[0160] like Figure 3 , Fig.16 , Fig.17 and Fig.18 As shown, the reinforcement sleeve 24 also includes two left and right bottom joint steel bar groups, each of which is arranged at the bottom of one of the support grooves 6;

[0161] Each of the bottom joint steel bar groups includes multiple groups of joint steel bars 3-5 arranged from front to back along the longitudinal extension direction of the tunnel, each group of the joint steel bars 3-5 includes two left and right joint steel bars 3-5 arranged on the same tunnel cross section, and the two joint steel bars 3-5 are arranged vertically; each of the joint steel bars 3-5 is divided into a lower anchoring section and an upper exposed section located above the lower anchoring section by the bottom surface of the support groove 6, and the lower anchoring section is anchored in the secondary lining 1 of the tunnel; the lower parts of the two upper exposed sections in each group of the joint steel bars 3-5 are connected by a horizontal connecting bar 3-6; all the joint steel bars 3-5 in each of the bottom joint steel bar groups are arranged in two left and right columns, and each column of the joint steel bars 3-5 includes multiple joint steel bars 3-5 arranged from front to back along the longitudinal extension direction of the tunnel;

[0162] The upper exposed section and horizontal connecting bars 3 - 6 in the bottom joint steel bar group are cast in the concrete sleeve 8 .

[0163] Among them, the anchor head 3-42 of the anchor stirrup 3-4 can effectively increase the anchoring strength of the anchor stirrup 3-4, and the hook 3-41 can be easily, quickly and securely hung on the inner annular steel bar 3-3, thereby easily completing the installation process of the inner annular steel bar 3-3.

[0164] During actual installation, multiple longitudinal steel bars 3-1 are arranged on the same arch surface. Moreover, the longitudinal steel bars 3-1 are connected to the outer annular steel bars 3-2 via steel bar insulation clips. In this embodiment, the steel bar insulation clips are cross insulation clips.

[0165] In this embodiment, the two bottom joint steel bar groups are arranged symmetrically.

[0166] In actual construction, the plurality of longitudinal steel bars 3-1 are evenly arranged, and the circumferential spacing between two adjacent longitudinal steel bars 3-1 is 1.8m to 2.2m. The plurality of anchoring stirrups 3-4 in each circumferential steel bar group are evenly arranged, and the circumferential spacing between two adjacent anchoring stirrups 3-4 in each circumferential steel bar group is 20cm to 30cm.

[0167] In this embodiment, the circumferential spacing between two adjacent longitudinal reinforcements 3-1 is 2m. The circumferential spacing between two adjacent anchoring stirrups 3-4 in each circumferential reinforcement group is 25cm.

[0168] During actual construction, the circumferential spacing between two adjacent longitudinal reinforcements 3-1 and the circumferential spacing between two adjacent anchor stirrups 3-4 in each circumferential reinforcement group can be adjusted accordingly according to specific needs.

[0169] In order to improve the anchoring strength, the thickness of the secondary lining of the arch wall is 40cm to 50cm, and the length of the outer anchoring section is 18cm to 22cm. In this embodiment, the thickness of the secondary lining of the arch wall is 45cm, and the length of the outer anchoring section is 20cm. During actual construction, the length of the outer anchoring section can be adjusted accordingly according to specific needs.

[0170] In order to facilitate construction and achieve a good jointing effect, multiple groups of the jointing steel bars 3-5 in each bottom jointing steel bar group are evenly arranged, and the distance between two adjacent groups of the jointing steel bars 3-5 in each bottom jointing steel bar group is 18cm to 22cm.

[0171] In this embodiment, the spacing between two joint steel bars 3-5 in each group of joint steel bars 3-5 is the same as the spacing between the longitudinal steel bars 3-1 and the outer annular steel bars 3-2. In addition, each group of joint steel bars 3-5 is located between two adjacent annular steel bar groups.

[0172] The lengths of the lower anchoring section and the upper exposed section are both 25 cm to 35 cm. In this embodiment, the lengths of the lower anchoring section and the upper exposed section are both 30 cm. During actual construction, the lengths of the lower anchoring section and the upper exposed section can be adjusted accordingly according to specific needs.

[0173] In this embodiment, the thickness of the steel bar protective layer of the concrete lining 8 is not less than 5 cm. The concrete lining 8 is a cast-in-place concrete structure and its cross section is arched.

[0174] The vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 is not less than 5 cm. In this embodiment, the vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 is 5 cm. During actual construction, the vertical spacing between the bottom surface of the support groove 6 and the upper surface of the water ditch cable groove 7 can be adjusted accordingly according to specific needs.

[0175] In this embodiment, the longitudinal steel bars 3-1, the outer annular steel bars 3-2 and the inner annular steel bars 3-3 are all continuous steel bars.

[0176] In this embodiment, the distance between two adjacent annular steel bar groups in the arched steel bar structure is 15 cm to 20 cm.

[0177] During actual construction, the distance between two adjacent annular steel bar groups in the arched steel bar structure can be adjusted accordingly according to specific needs.

[0178] like Fig.19 , Fig. 20 As shown, the concrete lining 8 is divided into 7 lining casting sections along the circumferential direction, and the 7 lining casting sections are arranged along the longitudinal extension direction of the tunnel; the 7 lining casting sections include an arch crown casting section 8-1, two symmetrically arranged upper arch waist casting sections 8-2, two symmetrically arranged lower arch waist casting sections 8-3 and two symmetrically arranged side wall casting sections 8-4. The arch crown casting section 8-1, the upper arch waist casting section 8-2, the lower arch waist casting section 8-3 and the side wall casting section 8-4 are arranged from top to bottom. , the two upper arch waist casting sections 8-2 are symmetrically connected to the left and right sides of the arch crown casting section 8-1, and each of the lower arch waist casting sections 8-3 is connected between one of the arch crown casting sections 8-1 and one of the side wall casting sections 8-4; each of the side wall casting sections 8-4 is located inside the side wall of the tunnel section 2 to be rectified, and the vertical height of the side wall casting section 8-4 is 3m to 3.5m; the cross sections of the upper arch waist casting section 8-2, the lower arch waist casting section 8-3 and the arch crown casting section 8-1 are all arc-shaped;

[0179] The tunnel secondary lining 1 is provided with an arched formwork for forming the concrete casing 8;

[0180] Combination Fig.21 , Fig. 22 , Fig.23 and Fig.24The arch formwork is assembled by an arch forming formwork 9-1 for forming the arch casting section 8-1, two upper arch waist forming formworks 9-2 symmetrically arranged on the left and right and forming the upper arch waist casting section 8-2, two lower arch waist forming formworks 9-3 symmetrically arranged on the left and right and forming the lower arch waist casting section 8-3, and two side wall forming formworks 9-4 symmetrically arranged on the left and right and forming the side wall casting section 8-4. The cross sections of the arch forming formwork 9-1, the upper arch waist forming formwork 9-2 and the lower arch waist forming formwork 9-3 are all arc-shaped; the cross-sectional shape of the arch forming formwork 9-1 is the same as the cross-sectional shape of the inner wall of the arch casting section 8-1, and the upper arch waist forming formwork 9 -2 has the same cross-sectional shape as the inner wall cross-sectional shape of the upper arch waist casting section 8-2, the cross-sectional shape of the lower arch waist forming template 9-3 is the same as the inner wall cross-sectional shape of the lower arch waist casting section 8-3, and the cross-sectional shape of the side wall forming template 9-4 is the same as the inner wall cross-sectional shape of the side wall casting section 8-4; the two upper arch waist forming templates 9-2 are symmetrically arranged below the left and right sides of the arch crown forming template 9-1, each of the lower arch waist forming templates 9-3 is located between one of the upper arch waist forming templates 9-2 and one of the side wall forming templates 9-4, and the bottom of each of the side wall forming templates 9-4 is supported on the ditch cable trough 7 in the tunnel section 2 to be rectified, and the ditch cable trough 7 is a concrete trough;

[0181] The arch crown forming template 9-1, the upper arch waist forming template 9-2, the lower arch waist forming template 9-3 and the side wall forming template 9-4 are all sleeve forming templates; the sleeve forming template includes a steel template 10, a plurality of template stiffening ribs 11 arranged inside the steel template 10 and a plurality of template tie rods 12 for fixing the steel template 10 to the secondary lining of the arch wall, the plurality of template stiffening ribs 11 are arranged in parallel and arranged from front to back along the longitudinal extension direction of the tunnel, and each template stiffening rib 11 is arranged at the required On a tunnel cross section of the tunnel section 2, the shape of each template stiffening rib 11 is the same as the cross-sectional shape of the steel template at the position where it is arranged; each template tie rod 12 is arranged vertically to the inner side wall of the arch wall secondary lining at the position where it is arranged, the inner end of each template tie rod 12 is anchored to the arch wall secondary lining, and the outer end of each template tie rod 12 extends to the inner side of the steel template 10, and the steel template 10 is provided with a plurality of through holes for the template tie rod 12 to extend;

[0182] like Fig.25As shown, the vault casting structure includes a plurality of vertical grouting pipes 15 arranged from front to back along the longitudinal extension direction of the tunnel, and the plurality of vertical grouting pipes 15 are arranged on the same vertical plane and are located directly below the vault of the tunnel section 2 to be rectified, and the plurality of vertical grouting pipes 15 are evenly arranged; the upper end of each vertical grouting pipe 15 extends above the vault forming template 9-1, and the bottom end of each vertical grouting pipe 15 extends below the vault forming template 9-1, and a plurality of grouting holes for installing the vertical grouting pipes 15 are opened from front to back in the middle of the vault forming template 9-1.

[0183] In this embodiment, the arch template also includes two front and rear end templates, both of which are wooden templates and are arranged on the front and rear sides of the arch template respectively, and each of the end templates is arched. Each of the end templates is located on a tunnel cross section of the tunnel section 2 to be rectified.

[0184] In order to ensure the supporting effect of the side wall forming template 9 - 4 , a cover plate is provided on the notch of the ditch cable trough 7 .

[0185] During actual construction, the central angles of the upper arch waist casting section 8-2 and the lower arch waist casting section 8-3 are 25° to 35°, and the central angle of the arch crown casting section 8-1 is 30° to 45°. In this embodiment, the vertical height of the side wall casting section 8-4 is 3.3m, the vertical height of the lower arch waist casting section 8-3 is 2.95m, and the vertical height of the upper arch waist casting section 8-2 is 1.85m. During actual construction, the vertical height of the side wall casting section 8-4 and the arc length and vertical height of the upper arch waist casting section 8-2, the lower arch waist casting section 8-3 and the arch crown casting section 8-1 can be adjusted accordingly according to specific needs.

[0186] In this embodiment, the steel template 10 and the template stiffening ribs 11 on its outer side are fixedly connected by welding.

[0187] In order to further reinforce the sleeve lining forming template, the sleeve lining forming template also includes a plurality of longitudinal reinforcement plates 18 arranged from top to bottom, and the plurality of longitudinal reinforcement plates 18 are arranged horizontally and along the longitudinal extension direction of the tunnel, and each longitudinal reinforcement plate 18 is arranged vertically with the outer wall of the steel template 10 at its arrangement position. Each template stiffening rib 11 on the outer side of the sleeve lining forming template is divided into a plurality of stiffening rib segments by the plurality of longitudinal reinforcement plates 18. In this embodiment, the longitudinal reinforcement plates 18 are fixedly connected to the steel template 10 by welding. The longitudinal reinforcement plates 18 are long strip steel plates.

[0188] The tunnel section 2 to be rectified is a tunnel section that has defects on the tunnel secondary lining 1 and needs to be rectified. In this embodiment, the excavation width of the tunnel section 2 to be rectified is 15m-16m, and the excavation height of the tunnel section 2 to be rectified is 12.5m-13.5m.

[0189] For the sake of easy processing and convenient fixing, the template tie rod 12 is a screw rod.

[0190] In this embodiment, the template tie rod 12 is a threaded steel bar with a diameter of Φ14mm. When installing the template tie rod 12, first drill holes on the secondary lining of the arch wall, and anchor the template tie rod 12 in the drilled holes on the secondary lining of the arch wall through an anchoring agent; the anchoring depth of the template tie rod 12 is not less than 20cm. Before pouring concrete on the concrete sleeve 8, ensure that the pull-out force of each template tie rod 12 is not less than 20kN.

[0191] In order to make the fixing of the sleeve lining forming template easy and reliable, all the template tie rods 12 on each of the sleeve lining forming templates are arranged in multiple rows from front to back, and each row of the template tie rods 12 and a template stiffening rib 11 are arranged on the same tunnel cross-section of the tunnel section 2 to be renovated; each row of the template tie rods 12 includes a plurality of template tie rods 12 arranged from top to bottom on the same tunnel cross-section, and the outer end of each template tie rod 12 extends out from the steel template 10 and the template stiffening rib 11; each of the template stiffening ribs 11 is provided with a plurality of through holes for the template tie rods 12 to extend out.

[0192] In addition, a limiting member 13 is installed at the outer end of each template tie rod 12 . The limiting member 13 is located inside the template stiffening rib 11 . A pad 14 is installed between the limiting member 13 and the template stiffening rib 11 .

[0193] In this embodiment, the pad 14 is a cubic pad block. In addition, the pad 14 is a wooden pad block.

[0194] In this embodiment, the template stiffening rib 11 is a channel steel, and the use of the channel steel can effectively reinforce the steel template 10.

[0195] The notches of the template stiffening ribs 11 face inwards, and the webs of the template stiffening ribs 11 are provided with a plurality of through holes for the template tie rods 12 to extend out. During actual construction, the pads 14 are arranged in the notches of the template stiffening ribs 11.

[0196] In this embodiment, the structures and sizes of the plurality of vertical grouting pipes 15 are the same. The spacing between two adjacent vertical grouting pipes 15 is 1 m. During actual construction, the spacing between two adjacent vertical grouting pipes 15 can be adjusted accordingly according to specific needs.

[0197] like Fig.25 As shown, in this embodiment, the cross section of the vertical grouting pipe 15 is circular and the diameter gradually decreases from top to bottom. In addition, the vertical grouting pipe 15 is a PVC pipe, which is very simple in actual construction, convenient for grouting, and has good use effect.

[0198] In this embodiment, the tunnel secondary lining 1 of the tunnel section 2 to be repaired has defects such as falling blocks of the lining surface due to concrete extrusion, hollowing of the upper part of the secondary lining concrete, and twisting and deformation of the steel frame. The upper end of the vertical grouting pipe 15 is flush with the arch of the concrete sleeve 8, which can effectively ensure the concrete pouring density of the concrete sleeve 8 and the concrete pouring quality of the concrete sleeve 8. At the same time, the cavity 19 to be filled formed between the arch of the tunnel secondary lining 1 and the arch of the concrete sleeve 8 after the upper part of the secondary lining concrete is hollowed out can be poured, and the density of the concrete poured in the cavity 19 to be filled can be ensured.

[0199] like Fig.26 As shown, in order to further increase the connection strength and connection quality between the concrete sleeve 8 and the secondary lining of the arch wall, a lower chiseling groove 16 is opened on the upper outer side of each upper arch waist casting section 8-2. The lower chiseling groove 16 is a horizontal groove formed by chiseling the concrete of the secondary lining of the arch wall. The lower chiseling groove 16 is arranged along the longitudinal extension direction of the tunnel and its upper surface is a horizontal plane. The two lower chiseling grooves 16 are symmetrically arranged;

[0200] An upper chiseled groove 17 is opened above the left and right sides of the arch crown casting section 8-1. The upper chiseled groove 17 is a horizontal groove formed by chiseling away the concrete in the secondary lining of the arch wall. The upper chiseled groove 17 is arranged along the longitudinal extension direction of the tunnel and its upper surface is a horizontal plane; the upper chiseled grooves 17 above the left and right sides of the arch crown casting section 8-1 are symmetrically arranged.

[0201] When the upper haunch casting section 8-2 is actually poured with concrete, the lower chiseled groove 16 is poured. Also, when the crown casting section 8-1 is poured with concrete, the upper chiseled groove 17 is poured.

[0202] In this embodiment, the length of the tunnel section 2 to be regulated is not more than 15 m.

[0203] like Fig. 27 A second lining treatment construction method for a karst stratum tunnel is shown, comprising the following steps:

[0204] Step 1: installing the steel arch frame: installing multiple steel arch frames 23 from back to front in the tunnel section 2 to be rectified along the longitudinal extension direction of the tunnel, and making each of the steel arch frames 23 fixedly supported on a cross section of the tunnel section 2 to be rectified;

[0205] The tunnel section 2 to be regulated is a tunnel section passing through a karst stratum;

[0206] Step 2, grouting anchoring construction: in the process of installing the multiple steel arch frames 23 from back to front in step 1, the multiple locking foot anchor rod groups in the grouting anchoring structure are constructed from back to front, and each locking foot anchor rod group is arranged on the outside of a steel arch frame 23 that has been installed; the construction methods of the multiple locking foot anchor rod groups are the same;

[0207] When constructing any of the locking foot anchor rod groups, the left and right locking foot anchor rods 22 in the locking foot anchor rod group are constructed symmetrically;

[0208] In this step, during the process of constructing the multiple locking anchor rod groups in the grouting anchor structure from back to front, the multiple system anchor rod groups in the grouting anchor structure are constructed from back to front, and each system anchor rod group is arranged outside a steel arch frame 23 that has been installed; the construction methods of the multiple system anchor rod groups are the same;

[0209] When any one of the system anchor rod groups is constructed, the multiple system anchor rods 9 in the system anchor rod group are constructed symmetrically.

[0210] After the construction of the plurality of locking foot anchor rod groups and the plurality of system anchor rod groups in the grouting anchoring structure is completed, the grouting anchoring structure is formed;

[0211] Step 3: roughening the inner wall of the tunnel secondary lining: roughening the inner wall of the tunnel secondary lining 1 of the tunnel section 2 to be rectified;

[0212] Step 4: Construction of the arched steel bar structure: construct the arched steel bar structure from back to front along the longitudinal extension direction of the tunnel, and fix the constructed arched steel bar structure to the multiple steel arch frames 23 in step 1;

[0213] Step 5, concrete lining construction: concrete pouring construction is performed on the concrete lining 8 to obtain a formed concrete lining 8, and the multiple steel arch frames 23 in step 1 and the arched steel bar structure in step 4 are poured into the concrete lining 8.

[0214] In this embodiment, when any one of the locking foot anchor rod groups is constructed in step 2, when any one of the locking foot anchor rods 22 in each of the locking foot anchor rod groups is constructed, the following steps are included:

[0215] Step A1, drilling: using a drilling device to drill the locking foot anchor rod installation hole of the currently constructed locking foot anchor rod 22 to obtain the constructed locking foot anchor rod installation hole;

[0216] Step A2, anchor rod installation: install the currently constructed locking foot anchor rod 22 from the inside to the outside into the locking foot anchor rod installation hole described in step A1, and fix the outer end of the installed locking foot anchor rod 22 on one of the steel arch frames 23;

[0217] Step A3, grouting: injecting cement slurry into the outer surrounding rock of the tunnel section 2 to be rectified through the locking anchor rod 22 described in step A2, and grouting reinforcement is performed on the outer surrounding rock of the tunnel section 2 to be rectified at the location where the locking anchor rod 22 is located;

[0218] Step A4, plugging the hole opening: After the grouting in step A3 is completed, the hole opening of the locking foot anchor rod installation hole is plugged to complete the construction process of the currently constructed locking foot anchor rod 22;

[0219] When any one of the system anchor rod groups is constructed in step 2, when any one of the system anchor rods 9 in each of the system anchor rod groups is constructed, the following steps are included:

[0220] Step B1, drilling: using a drilling device to drill the system anchor bolt installation hole of the currently constructed system anchor bolt 9 to obtain the constructed system anchor bolt installation hole;

[0221] Step B2, anchor rod installation: install the currently constructed system anchor rod 9 from the inside to the outside into the system anchor rod installation hole described in step B1, and fix the outer end of the installed system anchor rod 9 on one of the steel arch frames 23;

[0222] Step B3, hole plugging: After the system anchor rod 9 is installed in step B2, the hole of the system anchor rod installation hole where the system anchor rod 9 is located is plugged to obtain a hole plugging structure; at the same time, an exhaust pipe is installed in the hole plugging structure, the outer end of the exhaust pipe extends into the system anchor rod installation hole, and the inner end of the exhaust pipe extends to the outside of the hole plugging structure;

[0223] Step B4, grouting: inject cement slurry into the outer surrounding rock of the tunnel section 2 to be rectified through the system anchor rod 9 described in step B3, and perform grouting reinforcement on the outer surrounding rock of the tunnel section 2 to be rectified at the position where the system anchor rod 9 is located.

[0224] It can be seen from the above content that in order to further ensure the anchoring effect, the system anchor rod 9 is a grouting anchor rod that is sealed first and then grouting. The orifice of each system anchor rod installation hole is provided with an orifice sealing structure, and the orifice of each system anchor rod installation hole is installed with an exhaust pipe. In step B3, the orifice of the system anchor rod installation hole is sealed with an anchoring agent. The sealing length of the system anchor rod installation hole is greater than 30cm, and the exhaust pipe is exposed for 1.5m to 2m (convenient for receiving slurry with a bucket when returning slurry). In step B4, when grouting is performed through the system anchor rod 9, after the exhaust pipe at the orifice of the system anchor rod installation hole returns slurry, the exhaust pipe is quickly tied, and the grouting is supplemented for 5 minutes or the grouting pressure of the system anchor rod 9 reaches 0.8MPa to end the grouting. After the grouting is completed, the excessively long part of the system anchor rod 9 is cut off. Since the arch of tunnel section 2 to be repaired is a seriously damaged area, and the system anchor rods 9 are all grouted from bottom to top, in order to ensure the grouting and anchoring effect, the system anchor rods 9 all adopt a grouting method of sealing the hole first and then grouting, which can effectively ensure the grouting density of each system anchor rod 9 and ensure the anchoring quality and anchoring strength.

[0225] The locking foot anchor rod 22 is a grouting anchor rod that is grouted first and then sealed. When the opening of the locking foot anchor rod installation hole is blocked in step A4, an anchoring agent is used for blocking; and when grouting is performed in step A3, when the opening of the locking foot anchor rod installation hole has grouting or the grouting pressure of the locking foot anchor rod 22 reaches 1MPa, the grouting is terminated, and the actual operation is very simple.

[0226] In this embodiment, the inner ends of the locking foot anchor rod 22 and the system anchor rod 9 are both installed with fixing anchors, and the fixing anchors are cast in the concrete lining.

[0227] To further ensure a good connection between the new and old concrete structures (i.e., the tunnel secondary lining 1 and the concrete sleeve 8), when roughening the inner wall of the tunnel secondary lining 1 of the tunnel section 2 to be rectified in step 3, the inner surface of the tunnel secondary lining 1 needs to be roughened. After roughening, the roughened area is first cleaned with a wire brush and then cleaned with high-pressure water. In this embodiment, after roughening, the inner surface of the tunnel secondary lining 1 has a concave-convex difference of not less than 4 mm.

[0228] Before the concrete lining is constructed in step 5, the plurality of steel arch frames 23, the arched steel bar structure and the two left and right bottom joint steel bar groups are installed respectively.

[0229] When installing multiple steel arch frames 23 in step one, the installation methods of multiple steel arch frames 23 are the same. Before installing any steel arch frame 23, first, according to the layout positions of the fasteners 20-2 for fixing the steel arch frame 23, use a drilling rig to drill the anchor holes of each fastener 20-2 respectively; after the anchor holes of all the fasteners 20-2 for fixing the steel arch frame 23 are drilled, the steel arch frame 23 is supported, and the supported steel arch frame 23 is fixed by multiple arch frame fixings, completing the installation process of one steel arch frame 23, and the actual installation is simple and the fixation is reliable. After the installation of one steel arch frame 23 is completed, the steel arch frame 23 is connected to the adjacent steel arch frame 23 by multiple longitudinal connecting steel bars 21. Each of the fasteners 20-2 in the arch frame fixings is fixed by anchoring glue. To provide an anchoring effect, the anchoring length of the fastener 20 - 2 is greater than 15 cm.

[0230] In order to strengthen the foundation stability of the casing lining 24 and ensure the improvement effect of the tunnel secondary lining, local grooves are chiseled on the existing secondary lining concrete (i.e., the tunnel secondary lining 1), specifically, the lower groove 16 and the upper groove 17 are chiseled, and at the same time, the system anchor rod 9 and the locking foot anchor rod 22 are used for grouting and anchoring. The grouting angle of the system anchor rod 9 is perpendicular to the existing secondary lining section, and the cement slurry is grouted densely.

[0231] In this embodiment, when the arched steel bar structure is constructed in step 4, multiple annular steel bar groups are installed from front to back along the longitudinal extension direction of the tunnel, and the installation methods of multiple annular steel bar groups are the same. When installing any of the annular steel bar groups, first anchor the multiple anchoring hoops 3-4 in the annular steel bar group; after the multiple anchoring hoops 3-4 are anchored, the outer annular steel bar 3-2 is installed and supported on the inner wall of the tunnel secondary lining 1, and at the same time, the outer ends of the internal connection sections of each anchoring hoops 3-4 are connected to the outer annular steel bar 3-2 by binding or welding, completing the installation process of the outer annular steel bar 3-2; after the installation of the outer annular steel bar 3-2 is completed, the inner annular steel bar 3-3 is installed; when installing the inner annular steel bar 3-3, the hooks 3-41 of each anchoring hoops 3-4 are hooked on the inner annular steel bar 3-3 and the two are fixed by spot welding.

[0232] After all the inner circumferential steel bars 3-3 and the multiple steel arch frames 23 in the arched steel bar structure are installed, the multiple longitudinal steel bars 3-1 are installed respectively to complete the installation process of the arched steel bar structure. The installation method of the multiple longitudinal steel bars 3-1 is the same. When installing any longitudinal steel bar 3-1, the longitudinal steel bar 3-1 is connected to each inner circumferential steel bar 3-3 in the arched steel bar structure, and the longitudinal steel bar 3-1 is welded and fixed to the inner wing plates 23-2 of the multiple steel arch frames 23.

[0233] During the construction of the arched steel bar structure, the joint steel bars 3-5 in the two bottom joint steel bar groups are anchored respectively.

[0234] After the installation of the plurality of steel arch frames 23, the arched steel bar structure and the two left and right bottom joint steel bar groups is completed, step five is entered to cast concrete for the concrete sleeve 8.

[0235] When the concrete lining is constructed in step 5, the arch formwork is used for construction. In addition, before the concrete lining is constructed in step 5, all the formwork tie rods 12 for fixing the arch top forming formwork 9-1, the upper arch waist forming formwork 9-2, the lower arch waist forming formwork 9-3 and the side wall forming formwork 9-4 are fixed on the secondary lining of the arch wall.

[0236] When the concrete sleeve is constructed in step five, the formwork is supported in four times; first, the two side wall forming templates 9-4 are installed respectively, and the two side wall forming templates 9-4 are used to symmetrically cast the left and right side wall casting sections 8-4; then the two lower arch waist forming templates 9-3 are installed respectively, and the two lower arch waist forming templates 9-3 are used to symmetrically cast the left and right lower arch waist casting sections 8-3; then, the two upper arch waist forming templates 9-2 are installed respectively, and the two upper arch waist forming templates 9-2 are used to symmetrically cast the left and right upper arch waist casting sections 8-2; finally, the arch crown forming template 9-1 and the plurality of vertical grouting pipes 15 are installed, and the arch crown casting section 8-1 is cast with concrete using the plurality of vertical grouting pipes 15 to complete the construction process of the concrete sleeve 8.

[0237] During the actual construction process, when pouring concrete for the side wall casting section 8-4, the lower arch waist casting section 8-3 and the upper arch waist casting section 8-2, an inserted vibrating rod was used for tamping and the concrete was poured in layers from bottom to top with a layer thickness of 100 cm.

[0238] When pouring concrete for the vault pouring section 8-1, an inserted vibrating rod is used and vibrated through the vibrating holes opened on the end mold to ensure the quality of concrete pouring.

[0239] To ensure the molding quality of the concrete lining 8, it is strictly forbidden to remove the side wall forming formwork 9-4 when pouring the lower arch waist pouring section 8-3; and, it is strictly forbidden to remove the lower arch waist forming formwork 9-3 when pouring the upper arch waist pouring section 8-2; accordingly, it is strictly forbidden to remove the upper arch waist forming formwork 9-2 when pouring the vault pouring section 8-1.

[0240] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A karst stratum tunnel secondary lining treatment construction structure based on casing lining, characterized by: It comprises a grouting anchoring structure for supporting the arch wall of the tunnel section (2) to be rectified and a reinforcing sleeve (24) for reinforcing the arch wall of the tunnel section (2) to be rectified, wherein the reinforcing sleeve (24) is arranged on the inner side of the tunnel secondary lining (1) of the tunnel section (2) to be rectified, and the grouting anchoring structure is arranged on the outer side of the reinforcing sleeve (24); The tunnel secondary lining (1) is a full-section support structure for full-section support of the tunnel section (2) to be rectified, and the tunnel secondary lining (1) is a reinforced concrete lining; the tunnel secondary lining (1) comprises an arch wall secondary lining for supporting the arch wall of the tunnel section (2) to be rectified and a tunnel invert arranged at the bottom of the tunnel section (2) to be rectified, and the tunnel invert is located directly below the arch wall secondary lining and the two are connected as a whole; an initial tunnel support structure (5) for initial support of the tunnel section (2) to be rectified is arranged outside the tunnel secondary lining (1), and the initial tunnel support structure (5) and the tunnel secondary lining (1) constitute a tunnel support structure of the tunnel section (2) to be rectified; the grouting anchor structure is fastened to the reinforcement sleeve (24) and the tunnel support structure as a whole; The reinforcement sleeve (24) comprises a concrete sleeve (8) cast by concrete, a plurality of steel arch frames (23) arranged from front to back in the longitudinal extension direction of the tunnel in the concrete sleeve (8), and an arched steel bar structure arranged in the concrete sleeve (8); the concrete sleeve (8) and the arched wall secondary lining arranged outside the concrete sleeve (8) are cast as one body, and the cross-sectional shape of the concrete sleeve (8) is the same as the cross-sectional shape of the arched wall secondary lining; the plurality of steel arch frames (23) and the arched steel bar structure are cast in the concrete sleeve (8); The plurality of steel arch frames (23) are evenly arranged, and each of the steel arch frames (23) is arranged on a tunnel cross section of the tunnel section (2) to be rectified; the plurality of steel arch frames (23) are supported on the inner wall of the tunnel secondary lining (1), and the structure and size of the plurality of steel arch frames (23) are the same; the steel arch frames (23) are arch supports supported in the secondary lining of the arch wall, and the cross-sectional shape of the steel arch frames (23) is the same as the cross-sectional shape of the secondary lining of the arch wall; the spacing between two adjacent steel arch frames (23) is d, wherein the value range of d is 0.8m to 1.2m; The grouting anchoring structure comprises a plurality of locking foot anchor rod groups for supporting the arch feet on the left and right sides of the tunnel section (2) to be rectified and a plurality of system anchor rod groups for supporting the arch portion of the tunnel section (2) to be rectified, wherein the plurality of locking foot anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel, the plurality of locking foot anchor rod groups have the same structure and are evenly arranged, and each of the locking foot anchor rod groups is located on a tunnel cross section of the tunnel section (2) to be rectified; the plurality of system anchor rod groups are arranged from front to back along the longitudinal extension direction of the tunnel and are evenly arranged, and each of the system anchor rod groups is located on a tunnel cross section of the tunnel section (2) to be rectified; The distance between two adjacent locking foot anchor rod groups is d, and each locking foot anchor rod group is arranged on the same tunnel cross section as a steel arch frame (23); each locking foot anchor rod group includes two groups of symmetrically arranged locking foot anchor rods (22) on the left and right; one group of locking foot anchor rods (22) is arranged on the outer side of the left arch foot of the steel arch frame (23), and the other group of locking foot anchor rods (22) is arranged on the outer side of the right arch foot of the steel arch frame (23); Each group of the locking foot anchor rods (22) comprises a plurality of locking foot anchor rods (22) arranged side by side on the same plane, and the plurality of locking foot anchor rods (22) in each group of the locking foot anchor rods (22) are arranged in parallel and arranged from front to back along the extension direction of the tunnel; each of the locking foot anchor rods (22) is gradually inclined downward from the inside to the outside and the angle between it and the horizontal plane is 15° to 25°, and the inner end of each of the locking foot anchor rods (22) is fixed on the steel arch frame (23) located on the inner side thereof; The spacing between two adjacent system anchor rod groups is 2d, and each system anchor rod group is arranged on the same tunnel cross section with a steel arch frame (23); each system anchor rod group includes a plurality of system anchor rods (9) uniformly arranged on the same tunnel cross section along the circumferential direction, and each system anchor rod (9) is arranged perpendicular to the inner wall of the tunnel secondary lining (1) at its position; the inner end of each system anchor rod (9) is fixed on the steel arch frame (23) located on the inner side thereof; the system anchor rods (9) of two adjacent system anchor rod groups are arranged in a staggered manner; The locking foot anchor rod (22) and the system anchor rod (9) are both straight anchor rods that enter the outer surrounding rock of the tunnel section (2) to be rectified after passing through the tunnel support structure. The locking foot anchor rod (22) and the system anchor rod (9) are both self-propelled anchor rods and both are grouting anchor rods. The bottoms of the left and right sides of the arch wall secondary lining are provided with a plurality of locking foot anchor rod installation holes for installing the locking foot anchor rod (22). The arch portion of the arch wall secondary lining is provided with a plurality of system anchor rod installation holes for installing the system anchor rod (9). The locking foot anchor rod installation holes and the system anchor rod installation holes are both straight holes drilled from the inside of the tunnel secondary lining (1) to the outside into the outer surrounding rock of the tunnel section (2) to be rectified.

2. The second lining renovation construction structure for karst stratum tunnel based on casing lining according to claim 1 is characterized by: The area where the system anchor rods (9) are arranged in the arch part of the secondary lining of the arch wall is the system anchor rod arrangement area, and the central angle of the system anchor rod arrangement area is A, wherein the value range of A is 135° to 145°.

3. The karst stratum tunnel secondary lining treatment construction structure based on casing lining according to claim 1 is characterized by: Each of the steel arch frames (23) is formed by bending an I-beam, the web of the I-beam is arranged vertically, one wing plate of the I-beam is an outer wing plate (23-1) supported on the inner wall of the secondary lining of the arch wall, and the other wing plate of the I-beam is an inner wing plate (23-2) located on the inner side of the outer wing plate (23-1); each of the steel arch frames (23) is fixedly installed on the inner wall of the secondary lining of the arch wall through an arch frame fixing structure; each of the arch frame fixing structures includes a plurality of arch frame fixing parts, the structures and sizes of the plurality of arch frame fixing parts are the same and they are all arranged on the same tunnel cross section of the tunnel section (2) to be rectified, the plurality of arch frame fixing parts are arranged along the outer contour line of the steel arch frame (23), and the plurality of arch frame fixing parts constitute a wing plate fixing structure for fixing the outer wing plate (23-1); Each of the arch frame fixing members comprises two symmetrically arranged front and rear fastening members (20), the two fastening members (20) being fastened to the front and rear sides of the outer wing plate (23-1) respectively; each of the fastening members (20) comprises a fastening member (20-1) fastened to the outer wing plate (23-1) and a fastener (20-2) for fixing the fastening member (20-1) to the tunnel support structure, the fastening member (20-1) being formed by bending a straight steel plate and being divided into a fastening member (20-2) fastened to the outer wing plate (23-1) and a fastening member (20-2) for fastening the fastening member (20-1) to the tunnel support structure; 1) and a fixing plate arranged on the inner wall of the secondary lining of the arch wall, the fixing plate is located on the outer side of the fixing plate, and the fastener (20-2) is installed on the fixing plate; each of the fasteners (20-2) is arranged vertically to the inner wall of the secondary lining of the arch wall at its position, and each of the fasteners (20-2) extends from the inside to the outside to the outside of the tunnel support structure; the fastener (20-2) is a chemical anchor bolt, and the fixing plate is provided with an installation hole for installing the chemical anchor bolt.

4. The second lining renovation construction structure for karst stratum tunnel based on casing lining according to claim 3 is characterized by: The arched steel bar structure comprises a plurality of annular steel bar groups arranged from front to back in the tunnel section (2) to be rectified along the longitudinal extension direction of the tunnel and a plurality of longitudinal steel bars (3-1) arranged horizontally, the plurality of longitudinal steel bars (3-1) having the same length and their front ends being arranged on the same tunnel cross section of the tunnel section (2) to be rectified; the plurality of annular steel bar groups have the same structure and size, each of the annular steel bar groups is arranged on a tunnel cross section of the tunnel section (2) to be rectified, the plurality of annular steel bar groups are fastened together by the plurality of longitudinal steel bars (3-1), and each of the longitudinal steel bars (3-1) is located on the inner side of the plurality of annular steel bar groups; Each of the steel arch frames (23) is arranged between two adjacent annular steel bar groups, and a plurality of annular steel bar groups are arranged between two adjacent steel arch frames (23). Each of the steel arch frames (23) is located outside the plurality of longitudinal steel bars (3-1), and the inner wing plates (23-2) of each of the steel arch frames (23) are welded and fixed to the plurality of longitudinal steel bars (3-1) as a whole. Each of the annular steel bar groups comprises a plurality of anchoring stirrups (3-4), an outer annular steel bar (3-2) arranged on the inner wall of the tunnel secondary lining (1), and an inner annular steel bar (3-3) arranged inside the outer annular steel bar (3-2); the outer annular steel bar (3-2) and the inner annular steel bar (3-3) in each of the annular steel bar groups are arranged on the same cross section of the tunnel section (2) to be rectified and both are arched steel bars arranged inside the arch wall secondary lining, and the shapes of the outer annular steel bar (3-2) and the inner annular steel bar (3-3) are as follows: The cross-sectional shape of each of the annular steel bar groups is the same as that of the secondary lining of the arch wall; the multiple anchoring stirrups (3-4) in each of the annular steel bar groups are arranged on the same cross-sectional surface of the tunnel section (2) to be rectified, the multiple anchoring stirrups (3-4) are arranged along the inner contour line of the secondary lining of the arch wall, and each of the anchoring stirrups (3-4) is arranged vertically to the inner wall of the secondary lining of the arch wall at the position where it is arranged; the multiple anchoring stirrups (3-4) in each of the annular steel bar groups are fastened and connected as a whole through the outer annular steel bar (3-2) and the inner annular steel bar (3-3); Each of the anchoring stirrups (3-4) is divided into an outer anchoring section anchored in the secondary lining of the arch wall and an inner connecting section located inside the outer anchoring section, the outer end of the outer anchoring section is an anchoring head (3-42) formed by bending; the inner end of the inner connecting section is a hook (3-41) formed by bending, the hook (3-41) is mounted on the inner annular steel bar (3-3) and the two are fixedly connected by spot welding; the outer end of the inner connecting section is connected to the outer annular steel bar (3-2); A plurality of longitudinal steel bars (3-1) are arranged along the inner contour line of the secondary lining of the arch wall, and each longitudinal steel bar (3-1) is connected to a plurality of outer annular steel bars (3-2) in the arch steel bar structure; The internal connection section, the longitudinal reinforcement (3-1), the outer annular reinforcement (3-2) and the inner annular reinforcement (3-3) in the arched reinforcement structure are all cast in a concrete lining (8).

5. The karst stratum tunnel secondary lining treatment construction structure based on casing lining according to claim 1 or 2, characterized in that: The bottoms of the left and right sides of the secondary lining of the arch wall are both provided with support grooves (6) for supporting the arch feet of the steel arch frame (23), and the support grooves (6) are installation grooves formed by chiseling away the concrete at the bottom of the secondary lining of the arch wall; the bottom surface of the support groove (6) is a horizontal surface, and the bottom surface of the support groove (6) is located below the upper surface of the water ditch cable trough (7) in the tunnel section (2) to be rectified; The left and right arch feet of the arched steel bar structure are both supported on the bottom surface of a support groove (6).

6. The second lining renovation construction structure for karst stratum tunnel based on casing lining according to claim 5 is characterized by: The reinforcement sleeve (24) further comprises two left and right bottom joint steel bar groups, each of which is arranged at the bottom of one of the support grooves (6); Each of the bottom joint steel bar groups comprises a plurality of groups of joint steel bars (3-5) arranged from front to back along the longitudinal extension direction of the tunnel, each group of the joint steel bars (3-5) comprises two left and right joint steel bars (3-5) arranged on the same tunnel cross section, and the two joint steel bars (3-5) are arranged vertically; each of the joint steel bars (3-5) is divided into a lower anchoring section and an upper exposed section located above the lower anchoring section by the bottom surface of the support groove (6), and the lower anchoring section is anchored in the secondary lining (1) of the tunnel; the lower parts of the two upper exposed sections in each group of the joint steel bars (3-5) are connected by a horizontal connecting bar (3-6); all the joint steel bars (3-5) in each of the bottom joint steel bar groups are arranged in two left and right columns, and each column of the joint steel bars (3-5) comprises a plurality of joint steel bars (3-5) arranged from front to back along the longitudinal extension direction of the tunnel; The upper exposed section and the horizontal connecting bars (3-6) in the bottom joint steel bar group are cast in the concrete sleeve (8).

7. The second lining treatment construction structure for karst stratum tunnel based on casing lining according to claim 1 or 2, characterized in that: The lengths of the locking foot anchor rod (22) and the system anchor rod (9) entering the surrounding rock outside the tunnel section (2) to be rectified are both not less than 4 m.

8. The second lining renovation construction structure for karst stratum tunnel based on casing lining according to claim 1 or 2, characterized in that: The excavation section of the tunnel section (2) to be rectified is greater than 100m 2 ; The concrete casing (8) is divided into seven casing casting sections along the circumferential direction, and the seven casing casting sections are arranged along the longitudinal extension direction of the tunnel; the seven casing casting sections include an arch crown casting section (8-1), two upper arch waist casting sections (8-2) arranged symmetrically on the left and right, two lower arch waist casting sections (8-3) arranged symmetrically on the left and right, and two side wall casting sections (8-4) arranged symmetrically on the left and right. The arch crown casting section (8-1), the upper arch waist casting section (8-2), the lower arch waist casting section (8-3) and the side wall casting section (8-4) are arranged from top to bottom, and the two The upper arch waist casting section (8-2) is symmetrically connected to the lower left and right sides of the arch crown casting section (8-1); each of the lower arch waist casting sections (8-3) is connected between one of the arch crown casting sections (8-1) and one of the side wall casting sections (8-4); each of the side wall casting sections (8-4) is located inside a side wall of the tunnel section (2) to be rectified; the vertical height of the side wall casting section (8-4) is 3m to 3.5m; the cross sections of the upper arch waist casting section (8-2), the lower arch waist casting section (8-3) and the arch crown casting section (8-1) are all arc-shaped; The tunnel secondary lining (1) is provided with an arched formwork for forming the concrete sleeve (8); The arch formwork is assembled from an arch forming formwork (9-1) for forming the arch casting section (8-1), two upper arch waist forming formworks (9-2) arranged symmetrically on the left and right and forming the upper arch waist casting section (8-2), two lower arch waist forming formworks (9-3) arranged symmetrically on the left and right and forming the lower arch waist casting section (8-3), and two side wall forming formworks (9-4) arranged symmetrically on the left and right and forming the side wall casting section (8-4). The cross sections of the arch forming formwork (9-1), the upper arch waist forming formwork (9-2) and the lower arch waist forming formwork (9-3) are all arc-shaped; the cross section of the arch forming formwork (9-1) is the same as the cross section of the inner wall of the arch casting section (8-1), and the upper arch waist forming formwork (9-1) is the same as the cross section of the inner wall of the arch casting section (8-1). 2) has a cross-sectional shape identical to the cross-sectional shape of the inner wall of the upper arch waist casting section (8-2), a cross-sectional shape identical to the cross-sectional shape of the inner wall of the lower arch waist casting section (8-3), and a cross-sectional shape identical to the cross-sectional shape of the inner wall of the side wall casting section (8-4); the two upper arch waist forming templates (9-2) are symmetrically arranged below the left and right sides of the arch crown forming template (9-1), each of the lower arch waist forming templates (9-3) is located between one of the upper arch waist forming templates (9-2) and one of the side wall forming templates (9-4), and the bottom of each of the side wall forming templates (9-4) is supported on a ditch cable trough (7) in the tunnel section (2) to be rectified, and the ditch cable trough (7) is a concrete trough; The arch crown forming template (9-1), the upper arch waist forming template (9-2), the lower arch waist forming template (9-3) and the side wall forming template (9-4) are all sleeve lining forming templates; the sleeve lining forming template includes a steel template (10), a plurality of template stiffening ribs (11) arranged inside the steel template (10) and a plurality of template tie rods (12) for fixing the steel template (10) to the secondary lining of the arch wall, the plurality of template stiffening ribs (11) are arranged in parallel and are arranged from front to back along the longitudinal extension direction of the tunnel, and each template stiffening rib (11) is evenly distributed. It is arranged on a tunnel cross section of a tunnel section (2) to be rectified, and the shape of each template stiffening rib (11) is the same as the cross-sectional shape of the steel template at the position where it is arranged; each template tie rod (12) is arranged vertically to the inner side wall of the arch wall secondary lining at the position where it is arranged, and the inner end of each template tie rod (12) is anchored to the arch wall secondary lining, and the outer end of each template tie rod (12) extends to the inner side of the steel template (10), and the steel template (10) is provided with a plurality of through holes for the template tie rods (12) to extend; The arch casting structure comprises a plurality of vertical grouting pipes (15) arranged from front to back along the longitudinal extension direction of the tunnel. The plurality of vertical grouting pipes (15) are arranged on the same vertical plane and are located directly below the arch of the tunnel section (2) to be rectified. The plurality of vertical grouting pipes (15) are evenly arranged. The upper end of each vertical grouting pipe (15) extends above the arch forming template (9-1), and the bottom end of each vertical grouting pipe (15) extends below the arch forming template (9-1). The middle part of the arch forming template (9-1) is provided with a plurality of grouting holes from front to back for installing the vertical grouting pipes (15).

9. A method for carrying out secondary lining treatment construction of a karst stratum tunnel using the construction structure as claimed in claim 1, characterized in that: The method comprises the following steps: Step 1: installing the steel arch frame: installing a plurality of steel arch frames (23) from the back to the front in the tunnel section (2) to be rectified along the longitudinal extension direction of the tunnel, and making each of the steel arch frames (23) fixedly supported on a cross section of the tunnel section (2) to be rectified; The tunnel section (2) to be regulated is a tunnel section passing through a karst stratum; Step 2, grouting and anchoring construction: in the process of installing the plurality of steel arch frames (23) from back to front in step 1, the plurality of locking foot anchor rod groups in the grouting and anchoring structure are constructed from back to front, and each locking foot anchor rod group is arranged outside a steel arch frame (23) that has been installed; the construction method of the plurality of locking foot anchor rod groups is the same; When constructing any one of the locking foot anchor rod groups, the left and right locking foot anchor rods (22) in the locking foot anchor rod group are constructed symmetrically; In this step, during the process of constructing the plurality of locking anchor rod groups in the grouting anchor structure from back to front, the plurality of system anchor rod groups in the grouting anchor structure are constructed from back to front, and each system anchor rod group is arranged outside a steel arch frame (23) that has been installed; the construction methods of the plurality of system anchor rod groups are the same; When any one of the system anchor rod groups is constructed, the plurality of system anchor rods (9) in the system anchor rod group are constructed symmetrically on the left and right; After the construction of the plurality of locking foot anchor rod groups and the plurality of system anchor rod groups in the grouting anchoring structure is completed, the grouting anchoring structure is formed; Step 3: roughening the inner wall of the tunnel secondary lining: roughening the inner wall of the tunnel secondary lining (1) of the tunnel section (2) to be rectified; Step 4: constructing the arched steel bar structure: constructing the arched steel bar structure from back to front along the longitudinal extension direction of the tunnel, and fixing and connecting the constructed arched steel bar structure to the plurality of steel arch frames (23) in step 1; Step 5, concrete casing construction: concrete casting construction is performed on the concrete casing (8) to obtain a constructed concrete casing (8), and the plurality of steel arch frames (23) in step 1 and the arched steel bar structure in step 4 are cast in the concrete casing (8).

10. The method for secondary lining construction of a karst stratum tunnel according to claim 9, characterized in that: When any of the locking foot anchor rod groups is constructed in step 2, when any of the locking foot anchor rods (22) in each of the locking foot anchor rod groups is constructed, the following steps are included: Step A1, drilling: using a drilling device to drill the locking foot anchor rod installation hole of the currently constructed locking foot anchor rod (22) to obtain the constructed locking foot anchor rod installation hole; Step A2, anchor rod installation: install the currently constructed locking foot anchor rod (22) from the inside to the outside into the locking foot anchor rod installation hole described in step A1, and fix the outer end of the installed locking foot anchor rod (22) on one of the steel arch frames (23); Step A3, grouting: injecting cement slurry into the outer surrounding rock of the tunnel section (2) to be rectified by means of the locking anchor rod (22) described in step A2, and grouting and reinforcing the outer surrounding rock of the tunnel section (2) to be rectified at the location of the locking anchor rod (22); Step A4, plugging the hole opening: after the grouting in step A3 is completed, the hole opening of the locking foot anchor rod installation hole is plugged to complete the construction process of the currently constructed locking foot anchor rod (22); When any one of the system anchor rod groups is constructed in step 2, when any one of the system anchor rods (9) in each of the system anchor rod groups is constructed, the following steps are included: Step B1, drilling: using a drilling device to drill the system anchor bolt installation hole of the currently constructed system anchor bolt (9) to obtain the constructed system anchor bolt installation hole; Step B2, anchor rod installation: install the currently constructed system anchor rod (9) from the inside to the outside into the system anchor rod installation hole described in step B1, and fix the outer end of the installed system anchor rod (9) on one of the steel arch frames (23); Step B3, hole opening plugging: after the system anchor rod (9) is installed in step B2, the hole opening of the system anchor rod installation hole where the system anchor rod (9) is located is plugged to obtain a hole opening plugging structure; at the same time, an exhaust pipe is installed in the hole opening plugging structure, the outer end of the exhaust pipe extends into the system anchor rod installation hole, and the inner end of the exhaust pipe extends to the outside of the hole opening plugging structure; Step B4, grouting: inject cement slurry into the outer surrounding rock of the tunnel section (2) to be rectified by the system anchor rod (9) described in step B3, and perform grouting reinforcement on the outer surrounding rock of the tunnel section (2) to be rectified at the location of the system anchor rod (9).

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