Tunnel lining structure in dilatant rheological or highly corrosive strata and its construction method

Abstract

The present invention provides a tunnel lining structure in a dilatant rheological or highly corrosive stratum, the tunnel lining structure comprising: an initial support layer; a corrosion-resistant energy-absorbing layer, which is filled with a corrosion-resistant energy-absorbing structure, the corrosion-resistant energy-absorbing structure comprising a polyethylene tube and two polyethylene hot-melt plugs, the interior of the polyethylene tube is filled with a porous ductile material, and the two polyethylene hot-melt plugs are fixed to both ends of the polyethylene tube; a waterproof layer, which is formed by overlapping polymer flexible waterproof rolls in sequence; a secondary lining layer, which is cast in sequence by a secondary lining structure; a plurality of drainage joints, which are arranged at the joints of any two adjacent secondary lining structures; wherein the initial support layer, the corrosion-resistant energy-absorbing layer, the waterproof layer and the secondary lining layer are arranged in sequence from the outside to the inside along the radial direction of the tunnel to form an integrated tunnel lining structure. The tunnel lining structure of the present invention has excellent anti-expansion, anti-rheological and anti-corrosion capabilities, and can improve the drainage level at the joints to ensure the long-term stability of the structure.

Description

Technical Field

[0001] The present invention belongs to the technical field of tunnel support, and in particular relates to a tunnel lining structure in a stratum containing expansion rheology or strong corrosion and a construction method thereof. Background Art

[0002] Tunnel support in strata with dilatant rheology or severe corrosion has always been a difficult problem in tunnel construction. After tunnel excavation, the hydraulic boundary changes, and the unique physical, mechanical, and chemical properties of the strata often induce large deformation problems. The tunnel secondary lining structure continuously bears the deformation pressure generated by the long-term aging of the surrounding rock. If the surrounding rock releases highly corrosive ions (sulfate ions, chloride ions, etc.) when exposed to water, they degrade and corrode the concrete lining, reducing its bearing capacity. As a result, tunnel lining structures passing through strata with dilatant rheology or severe corrosion often suffer from major engineering defects such as structural cracking, spalling, and floor heave when exposed to corrosive conditions for a long time. This compromises safety during tunnel construction and operation, leading to repeated repairs or even scrapping of many tunnels. Furthermore, effective technical measures have yet to be developed domestically or internationally.

[0003] In order to solve the problems of large deformation, long duration and corrosiveness of surrounding rock in dilatant rheological or highly corrosive strata, scholars have tried different optimization designs based on conventional support types, and proposed measures such as increasing support stiffness, setting foam concrete or extruded foam board buffer layers, and water-blocking with waterstops. However, the limitations of these optimization schemes are still very large, and no standardized and effective support system has been formed. Simply increasing the support stiffness will not only lead to a significant increase in costs, but also fail to fundamentally solve the problem. Over time, the problem will still occur. Ordinary foam concrete buffer layers will be rapidly eroded when exposed to corrosive aqueous solutions, and the erosion of the skeleton will reduce its energy absorption performance. The support resistance of the energy-absorbing section of the extruded foam board is often insufficient, and the support effect is unstable. In addition, the back-stick waterstop used at the joints of traditional cast-in-place reinforced concrete linings does not have a drainage function. Groundwater is easily accumulated at the joints of the two linings, and the water pressure increases accordingly, and the actual waterproofing effect is not ideal.

[0004] Therefore, how to enhance the anti-expansion, anti-rheological and anti-corrosion capabilities of tunnel lining structures in dilatant rheological or highly corrosive strata, improve the drainage level at the secondary lining joints, and ensure the long-term stability of the secondary lining structure are technical problems that technical personnel in this field urgently need to solve. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing technology lacks an effective support system for tunnels containing expansion rheology or strong corrosive strata, and has technical problems such as low energy absorption performance, lack of scientific quantitative design, poor support stability, and low waterproof effect.

[0006] In order to solve the above problems, the first aspect of the present invention provides a tunnel lining structure in a dilatant rheological or highly corrosive stratum, the tunnel lining structure comprising: an initial support layer; a corrosion-resistant energy-absorbing layer, which is filled with a plurality of corrosion-resistant energy-absorbing structures, the corrosion-resistant energy-absorbing structure comprising a polyethylene tube and two polyethylene hot-melt plugs, the interior of the polyethylene tube is filled with porous ductile material, and the two polyethylene hot-melt plugs are respectively fixed to the two ends of the polyethylene tube; a waterproof layer, which is formed by overlapping a plurality of polymer flexible waterproof membranes in sequence along the axial direction of the tunnel in a dilatant rheological or highly corrosive stratum; a secondary lining layer, which is formed by casting a plurality of secondary lining structures in sequence along the axial direction of the tunnel; a plurality of drainage joints, which are arranged at the joints of any two adjacent secondary lining structures, and the joints are filled with asphalt filling material; wherein the initial support layer, the corrosion-resistant energy-absorbing layer, the waterproof layer and the secondary lining layer are arranged in sequence from the outside to the inside along the radial direction of the tunnel to form an integrated tunnel lining structure.

[0007] In the first aspect, the design thickness δ of the corrosion-resistant energy-absorbing layer is determined by conducting a confined compression test on the corrosion-resistant energy-absorbing structure to obtain a stress-strain curve of the energy absorption stage of the corrosion-resistant energy-absorbing structure, and determining an energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure, wherein the energy absorption stage includes an elastic stage and a pressure-yielding platform stage; the energy absorption efficiency index η is set to: η = ΔV / V = SΔL / SL = ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure, S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure, ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure, ε P is the end point strain of the yield plateau stage; the surrounding rock of the tunnel is tested to determine the long-term aging deformation U of the surrounding rock L The long-term aging deformation U L Set to: U L =U S +U C Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock; determine the design thickness δ of the corrosion-resistant energy-absorbing layer; the design thickness δ of the corrosion-resistant energy-absorbing layer is set to: U A =U L -U R ; δ=U A / η; among them, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure, U R The reserved deformation amount of the secondary lining structure.

[0008] In the first aspect, the porous ductile material comprises polyurethane foam, polystyrene foam or foam rubber.

[0009] In the first aspect, the polyethylene tube has a diameter of 5-20 cm and a length of 1-6 m.

[0010] In the first aspect, the anti-drainage joint includes a back-sticked guide waterstop, a steel-edge embedded waterstop and a water filter strip; the back-sticked guide waterstop is arranged between the waterproof layer and the secondary lining layer, and the center position of one back-sticked guide waterstop of each anti-drainage joint is on the plane where the corresponding joint is located, and two water guide grooves are symmetrically opened on both sides of the middle part of the back-sticked guide waterstop, and the two water guide grooves are connected to the external drainage pipeline; half of the steel-edge embedded waterstop is buried in the interior of one of the two adjacent secondary lining structures, and the other half is buried in the interior of the other of the two adjacent secondary lining structures, and the steel-edge embedded waterstop is perpendicular to the joint; the water filter strip is located between the waterproof layer and the water guide groove, and the center position of the water filter strip is on the same horizontal line as the joint.

[0011] In the first aspect, the back-sticked diversion waterstop is made of corrosion-resistant EPDM rubber.

[0012] In the first aspect, the initial supporting layer is filled with ultra-high performance concrete.

[0013] In the first aspect, the secondary lining structure is filled with ultra-high performance concrete.

[0014] The second aspect of the present invention provides a construction method for a tunnel lining structure in a dilatant rheological or highly corrosive stratum, comprising the following steps: filling a porous ductile material inside a polyethylene tube, and then hot-melt sealing the two ends of the polyethylene tube with polyethylene hot-melt plugs to obtain a corrosion-resistant energy-absorbing structure; determining a design thickness δ of the corrosion-resistant energy-absorbing layer; after tunnel excavation, spraying ultra-high performance concrete onto the surrounding rock, and installing support facilities to form an initial support layer; after the initial support layer is closed into a ring, positioning and installing a plurality of corrosion-resistant energy-absorbing structures on the initial support layer to form the corrosion-resistant energy-absorbing layer; overlapping polymer flexible waterproof membranes in sequence on the corrosion-resistant energy-absorbing layer along the axial direction of the tunnel in the dilatant rheological or highly corrosive stratum to form a waterproof layer; alternately installing a plurality of drainage joints and a plurality of secondary lining structures in sequence along the axial direction of the tunnel, and when the secondary lining structure reaches the construction strength requirement, filling the joints between any two adjacent secondary lining structures with asphalt caulking material to form a secondary lining layer.

[0015] In the second aspect, determining the design thickness δ of the corrosion-resistant energy-absorbing layer includes: conducting a confined compression test on the corrosion-resistant energy-absorbing structure to obtain a stress-strain curve of the energy absorption stage of the corrosion-resistant energy-absorbing structure, and determining an energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure, wherein the energy absorption stage includes an elastic stage and a pressure-yielding platform stage; the energy absorption efficiency index η is set to: η = ΔV / V = SΔL / SL = ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure, S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure, ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure, ε P is the end point strain of the yield plateau stage; the surrounding rock of the tunnel is tested to determine the long-term aging deformation U of the surrounding rock L The long-term aging deformation U L Set to: U L =U S +U C Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock; determine the design thickness δ of the corrosion-resistant energy-absorbing layer; the design thickness δ of the corrosion-resistant energy-absorbing layer is set to: U A =U L -U R ; δ=U A / η; among them, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure, U R The reserved deformation amount of the secondary lining structure.

[0016] Beneficial effects: The tunnel lining structure in the expansion rheological or highly corrosive strata proposed by the present invention comprises an initial support layer, a corrosion-resistant energy-absorbing layer, a waterproof layer, a secondary lining layer and a number of drainage joints. By adding a corrosion-resistant energy-absorbing structure on the basis of the traditional tunnel support design, it can absorb the deformation pressure caused by the expansion rheological strata on the lining structure, and ensure that it will not be damaged when a large deformation occurs, effectively improving the anti-expansion, anti-rheological and anti-corrosion capabilities of the tunnel lining structure, overcoming the engineering disasters such as cracking and bottom heaving caused by the time-dependent large deformation of the tunnel passing through the expansion rheological or highly corrosive strata, and reducing the continuous load of the surrounding rock on the secondary lining, thereby reducing the rigidity of the secondary lining. The high-support requirements make the secondary lining design more economical and reasonable, greatly saving the project cost; the polyethylene material used in the polyethylene pipe and two polyethylene hot-melt plugs in the corrosion-resistant energy-absorbing structure has strong corrosion resistance, avoiding the risk of degradation of its own energy-absorbing performance due to corrosion, and the composite combination structure of the corrosion-resistant energy-absorbing structure can improve the strength, and its constant resistance pressure energy absorption effect is better than that of a single material, and it is light in weight and easy to install; in addition, by setting a waterproof layer and a drainage-proof joint, the possibility of corrosion and degradation of the secondary lining layer caused by the corrosive environment can be effectively reduced, and the drainage level at the joints between the secondary lining structures can be improved, effectively ensuring the long-term stability of the support system. The tunnel lining structure of the present invention not only has excellent anti-expansion, anti-rheology, anti-corrosion capabilities and support stability, but also has excellent drainage performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 A schematic structural diagram of the tunnel lining structure provided by the present invention;

[0020] Figure 2 for Figure 1 Schematic diagram of the structure of section Ⅰ-Ⅰ;

[0021] Figure 3 A schematic structural diagram of the corrosion-resistant energy-absorbing structure in the tunnel lining structure provided by the present invention;

[0022] Figure 4 for Figure 3 Schematic diagram of the structure of the middle II-II section;

[0023] Figure 5 A schematic structural diagram of a drainage joint in a tunnel lining structure provided by the present invention;

[0024] Figure 6 A schematic diagram of a stress-strain curve for a lateral compression test of a corrosion-resistant energy-absorbing structure.

[0025] Description of reference numerals:

[0026] 1. Initial support layer;

[0027] 2. Corrosion-resistant energy-absorbing layer; 21. Corrosion-resistant energy-absorbing structure; 211. Polyethylene pipe; 212. Polyethylene hot-melt plug; 213. Porous ductile material;

[0028] 3. Waterproof layer;

[0029] 4. Secondary lining layer; 41. Secondary lining structure; 42. Joints;

[0030] 5. Drainage joint; 51. Back-mounted diversion waterstop; 52. Steel-edge embedded waterstop; 53. Water filter strip; 54. Water guide trough. DETAILED DESCRIPTION

[0031] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0032] Throughout this specification, unless otherwise specified, the terms used herein should be understood as having the same meaning as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. In the event of any conflict, the present specification shall prevail.

[0033] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0034] Example 1

[0035] like Figure 1-5As shown, the present embodiment 1 provides a tunnel lining structure in a dilatant rheological or highly corrosive stratum, the tunnel lining structure comprising: an initial support layer 1; a corrosion-resistant energy-absorbing layer 2, which is filled with a plurality of corrosion-resistant energy-absorbing structures 21, the corrosion-resistant energy-absorbing structure 21 comprising a polyethylene tube 211 and two polyethylene hot-melt plugs 212, the interior of the polyethylene tube 211 is filled with a porous ductile material 213, the two polyethylene hot-melt plugs 212 are fixed to the two ends of the polyethylene tube 211 by hot-melt respectively; a waterproof layer 3, which is composed of a plurality of polymer flexible waterproof rolls The materials are overlapped in sequence along the axial direction of the tunnel in the expansion rheology or strong corrosion stratum; the secondary lining layer 4 is formed by casting a plurality of secondary lining structures 41 in sequence along the axial direction of the tunnel; a plurality of waterproof joints 5 are arranged at the joints 42 between any two adjacent secondary lining structures 41, and the joints 42 are filled with asphalt filling materials; wherein, the initial support layer 1, the corrosion-resistant energy-absorbing layer 2, the waterproof layer 3 and the secondary lining layer 4 are arranged in sequence from the outside to the inside along the radial direction of the tunnel to form the integrated tunnel lining structure.

[0036] Specifically, the tunnel lining structure in the dilatant rheological or highly corrosive strata proposed by the present invention comprises an initial support layer 1, a corrosion-resistant energy-absorbing layer 2, a waterproof layer 3, a secondary lining layer 4 and a plurality of drainage joints 5. By adding a corrosion-resistant energy-absorbing structure 21 on the basis of the traditional tunnel support design, the deformation pressure caused by the dilatant rheological strata on the lining structure can be absorbed, and it can be ensured that it will not be damaged when a large deformation occurs, thereby effectively improving the anti-expansion, anti-rheological and anti-corrosion capabilities of the tunnel lining structure, overcoming the engineering disasters such as cracking and bottom heaving caused by the time-dependent large deformation when passing through the dilatant rheological or highly corrosive strata, reducing the continuous load of the surrounding rock on the secondary lining, and thus reducing the support requirements for the secondary lining. The secondary lining design can be more economical and reasonable, greatly saving the project cost; the polyethylene material used in the polyethylene pipe 211 and the two polyethylene hot-melt plugs 212 in the corrosion-resistant energy-absorbing structure 21 has strong corrosion resistance, avoiding the risk of degradation of its own energy-absorbing performance due to corrosion, and the composite combination structure of the corrosion-resistant energy-absorbing structure 21 can improve the strength, and its constant resistance pressure energy absorption effect is better than that of a single material, and it is light in weight and easy to install; in addition, by providing a waterproof layer 2 and a drainage-proof joint 5, the possibility of corrosion and degradation of the secondary lining layer 4 caused by the corrosive environment can be effectively reduced, and the drainage level of the joints 42 between the secondary lining structures 41 can be improved, effectively ensuring the long-term stability of the support system. The tunnel lining structure of the present invention can form a closed support structure that integrates energy absorption and waterproofing, which not only has excellent anti-expansion, anti-rheology, anti-corrosion capabilities and support stability, but also has excellent drainage performance.

[0037] like Figure 6As shown, in some possible implementations, the design thickness δ of the corrosion-resistant energy-absorbing layer 2 is determined by conducting a confined compression test on the corrosion-resistant energy-absorbing structure 21 to obtain a stress-strain curve of the energy absorption stage of the corrosion-resistant energy-absorbing structure 21, and determining an energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure 21, wherein the energy absorption stage includes an elastic stage and a pressure-yielding platform stage; the energy absorption efficiency index η is set to: η = ΔV / V = SΔL / SL = ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure 21, S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure 21, ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure 21, ε P is the end point strain of the yield plateau stage; the surrounding rock of the tunnel is tested to determine the long-term aging deformation U of the surrounding rock L Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock; the long-term aging deformation U L Set to: U L =U S +U C ; Determine the design thickness δ of the corrosion-resistant energy-absorbing layer 2; The design thickness δ of the corrosion-resistant energy-absorbing layer is set to: U A =U L -U R ; δ=U A / η; among them, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure 21, U R It is the reserved deformation amount of the secondary lining layer 4.

[0038] This is because, by conducting a confined compression test on the corrosion-resistant energy-absorbing structure 21, the stress-strain curve of the energy-absorbing stage of the corrosion-resistant energy-absorbing structure 21 is obtained, the energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure 21 is determined, and then the expansion deformation U of the surrounding rock is calculated. S , the rheological deformation of the surrounding rock U C , the allowable deformation U of the corrosion-resistant energy-absorbing structure 21 A , the reserved deformation U of the secondary lining layer 4 R And long-term aging deformation U L The relationship between them is used to determine the design thickness δ of the corrosion-resistant energy-absorbing layer 2. By quantifying the design parameters of the corrosion-resistant energy-absorbing structure 21, the disadvantage of currently designing the thickness of the deformation energy-absorbing layer of tunnels with expansion rheology or strong corrosion strata based solely on engineering experience is solved, and the pressure-yielding support effect of the corrosion-resistant energy-absorbing structure 21 is guaranteed.

[0039] In some possible implementations, the porous ductile material 213 includes polyurethane foam, polystyrene foam, or foam rubber.

[0040] Those skilled in the art will understand that by using corrosion-resistant porous ductile materials 213 such as polyurethane foam, polystyrene foam or foam rubber, the corrosion-resistant energy-absorbing structure 21 can have excellent corrosion resistance, and by combining it with the polyethylene tube 211 and the polyethylene hot-melt plug 212, the strength and constant resistance pressure energy absorption performance of the corrosion-resistant energy-absorbing structure 21 can be improved.

[0041] In some possible implementations, the polyethylene tube 211 has a diameter of 5-20 cm, and a length of 1-6 m according to construction conditions.

[0042] This is because the polyethylene tube 211 has a diameter of 5-20 cm and a length of 1-6 m, which can meet the on-site installation space and production requirements, so that the multiple corrosion-resistant energy-absorbing structures 21 can better fill the corrosion-resistant energy-absorbing layer 2.

[0043] In some possible embodiments, the anti-drainage joint 5 includes a back-attached guide waterstop 51, a steel-edge embedded waterstop 52 and a water filter strip 53; the back-attached guide waterstop 51 is arranged between the waterproof layer 3 and the secondary lining layer 4, and the center position of one back-attached guide waterstop 51 of each anti-drainage joint 5 is on the plane where the corresponding joint 42 is located, and two water guide grooves 54 are symmetrically opened on both sides of the middle part of the back-attached guide waterstop 51, and the two water guide grooves 54 are connected to the external drainage pipeline; half of the steel-edge embedded waterstop 52 is buried in the interior of one of the two adjacent secondary lining structures 41, and the other half is buried in the interior of the other of the two adjacent secondary lining structures 41, and the steel-edge embedded waterstop 52 is perpendicular to the joint 42; the water filter strip 53 is located between the waterproof layer 3 and the water guide groove 54, and the center position of the water filter strip 53 is on the same horizontal line as the joint 42.

[0044] This is because a back-sticked diversion waterstop 51 is provided between the waterproof layer 3 and the secondary lining layer 4, which can not only play the role of waterproofing and water blocking of traditional waterstop, but also timely guide and discharge the water accumulated in the joint 42, reducing the overall water head around the secondary lining, enhancing the corrosion resistance of the lining, and greatly reducing the risk of large deformation induced by formation expansion rheology and lining corrosion, and ensuring the long-term stability of the tunnel support structure; by providing a water filter strip 53 between the waterproof layer 3 and the water guide trough 54, the sand and gravel flowing through during construction and operation can be blocked out, ensuring the drainage of the water guide trough 54; by burying the steel-edged embedded waterstop 52 inside the secondary lining structure 41, the waterproof and drainage performance of the secondary lining layer can be further improved. During the actual drainage process, the water in the tunnel surrounding rock flows through the filtered water strips 53 into the water guide groove 54, and then flows into the external drainage pipe through the water guide groove 54 to flow out of the tunnel, so as to prevent the water from penetrating into the secondary lining layer 4, reduce the possibility of erosion and degradation of the secondary lining layer 4 caused by the corrosive environment, and effectively ensure the long-term stability of the support system.

[0045] In some possible implementations, the back-sticked diversion waterstop 51 is made of corrosion-resistant EPDM rubber.

[0046] This is because the back-sticked guide waterstop 51 made of corrosion-resistant EPDM rubber has excellent corrosion resistance, which prevents the water flow in the tunnel surrounding rock from corroding the back-sticked guide waterstop 51 and then allows the water flow to flow through the back-sticked guide waterstop 51 into the secondary lining layer 4, causing erosion and degradation of the secondary lining layer 4.

[0047] In some possible implementations, the primary support layer 1 and the secondary lining structure 41 are both filled with ultra-high performance concrete.

[0048] Those skilled in the art will understand that ultra-high performance concrete has ultra-high durability and mechanical properties. Since the initial support layer 1 and the secondary lining structure 41 are both filled with ultra-high performance concrete, the corrosion rate of the lining can be greatly slowed down, ensuring long-term stability during tunnel construction and operation.

[0049] Example 2

[0050] The construction of tunnel lining structures in dilatant rheological or highly corrosive strata is carried out in the following steps:

[0051] The interior of the polyethylene tube 211 is filled with porous ductile material 213, and then the two ends of the polyethylene tube 211 are hot-melt sealed with polyethylene hot-melt plugs 212 to obtain a corrosion-resistant energy-absorbing structure 21; the design thickness δ of the corrosion-resistant energy-absorbing layer 2 is determined; after the tunnel is excavated, ultra-high performance concrete is sprayed on the surrounding rock, and support facilities are installed to form an initial support layer 1, wherein the ultra-high performance concrete is sprayed in the order of first wall and then arch, first up and then down, and the thickness of the sprayed layer is 10-20 cm; after the initial support layer 1 is closed into a ring, the initial support layer 1 is placed on the initial support layer 1. 1, a plurality of corrosion-resistant energy-absorbing structures 21 are positioned and installed on the tunnel 1 to form the corrosion-resistant energy-absorbing layer 2; a polymer flexible waterproof membrane is overlapped in sequence along the axial direction of the tunnel in the dilatant rheological or highly corrosive stratum to form a waterproof layer 3; a plurality of drainage joints 5 and a plurality of secondary lining structures 41 are alternately installed in sequence along the axial direction of the tunnel; when the secondary lining structure 41 reaches the construction strength requirement, the joint 42 between any two adjacent secondary lining structures 41 is filled with asphalt caulking material to form a secondary lining layer 4.

[0052] Among them, the back-sticked diversion waterstop 51 of the drainage joint 5 is constructed before the pouring of the secondary lining structure 41. Before the construction of the previous secondary lining structure 41, the back-sticked diversion waterstop 51 is glued and adhered to the waterproof layer 3 to fix it. When the previous secondary lining structure 41 is constructed, half of the steel-edge embedded waterstop 52 is buried in the interior of the secondary lining structure 41 with fixed steel bars. When the next secondary lining structure 41 is constructed, the other half of the steel-edge embedded waterstop 52 is buried in the interior of the next secondary lining structure 41 with fixed steel bars. When the secondary lining structure 41 reaches the construction strength requirements, the remaining gaps in the joints 42 between any two adjacent secondary lining structures 41 are filled with asphalt filling material 9.

[0053] Specifically, the construction method of the tunnel lining structure in the expansion rheological or strong corrosion stratum provided by the present invention can reduce the waiting time for the initial support layer 1 to be deformed and stabilized before the secondary lining layer 4 is supported by prefabricating the corrosion-resistant energy-absorbing structure 21 in advance, and close the ring early. The corrosion-resistant energy-absorbing structure 21 is lightweight and easy to install. The polyethylene hot-melt plug 212 is used to hot-melt seal the two ends of the polyethylene pipe 211, which can improve the sealing of the corrosion-resistant energy-absorbing structure 21, thereby enhancing the corrosion resistance of the corrosion-resistant energy-absorbing structure 21 and effectively ensuring the long-term energy absorption effect of the structure. The tunnel lining structure completed by the construction method of the present invention can form a closed support structure that integrates energy absorption and waterproofing, which not only has excellent anti-expansion, anti-rheological, anti-corrosion capabilities and support stability, but also has excellent drainage performance.

[0054] In some possible embodiments, determining the design thickness δ of the corrosion-resistant energy-absorbing layer 2 includes: conducting a confined compression test on the corrosion-resistant energy-absorbing structure 21 to obtain a stress-strain curve of the energy absorption stage of the corrosion-resistant energy-absorbing structure 21, and determining an energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure 21, wherein the energy absorption stage includes an elastic stage and a pressure-yielding platform stage; the energy absorption efficiency index η is set to: η = ΔV / V = SΔL / SL = ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure 21, S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure 21, ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure 21, ε P is the end point strain of the yield plateau stage; the surrounding rock of the tunnel is tested to determine the long-term aging deformation U of the surrounding rock L Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock; the long-term aging deformation U L Set to: U L =U S +U C ; Determine the design thickness δ of the corrosion-resistant energy-absorbing layer 2; The design thickness δ of the corrosion-resistant energy-absorbing layer is set to: U A =U L -U R ; δ=U A / η; among them, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure 21, U R It is the reserved deformation amount of the secondary lining layer 4.

[0055] It should be noted that the construction method of the tunnel lining structure in the dilatant rheological or highly corrosive strata provided in this embodiment 2 is the tunnel lining structure constructed therein, and its implementation principle and technical concept are exactly the same as those in embodiment 1. Therefore, for the parts not described in detail in this embodiment 2, please refer to embodiment 1 and will not be repeated here.

[0056] Finally, it should be noted that the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0057] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0058] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. Tunnel lining structure in dilatant rheological or highly corrosive strata, characterized in that: The tunnel lining structure comprises: Initial support layer (1); The corrosion-resistant energy-absorbing layer (2) is filled with a plurality of corrosion-resistant energy-absorbing structures (21), wherein the corrosion-resistant energy-absorbing structure (21) comprises a polyethylene tube (211) and two polyethylene hot-melt plugs (212), the interior of the polyethylene tube (211) is filled with a porous ductile material (213), and the two polyethylene hot-melt plugs (212) are respectively fixed to both ends of the polyethylene tube (211); The waterproof layer (3) is formed by overlapping a plurality of polymer flexible waterproof rolls in sequence along the axial direction of the tunnel in the dilatant rheological or highly corrosive stratum; A secondary lining layer (4) is formed by sequentially pouring a plurality of secondary lining structures (41) along the axial direction of the tunnel; A plurality of drainage joints (5) are provided at the joints (42) between any two adjacent secondary lining structures (41), and the joints (42) are filled with asphalt filling material; The initial support layer (1), the corrosion-resistant energy-absorbing layer (2), the waterproof layer (3) and the secondary lining layer (4) are sequentially arranged from the outside to the inside along the radial direction of the tunnel to form an integrated tunnel lining structure; The anti-drainage joint (5) comprises a back-sticking guide water stop (51), a steel edge embedded water stop (52) and a water filter strip (53); the back-sticking guide water stop (51) is arranged between the waterproof layer (3) and the secondary lining layer (4); the center position of one back-sticking guide water stop (51) of each anti-drainage joint (5) is on the plane where the corresponding joint (42) is located; two water guide grooves (54) are symmetrically opened on both sides of the middle of the back-sticking guide water stop (51); the two water guide grooves ( 54) is connected to the external drainage pipeline; half of the steel edge embedded water stop (52) is buried in one of the two adjacent secondary lining structures (41), and the other half is buried in the other of the two adjacent secondary lining structures (41), and the steel edge embedded water stop (52) is perpendicular to the joint (42); the water filter strip (53) is located between the waterproof layer (3) and the water guide groove (54), and the center position of the water filter strip (53) is on the same horizontal line as the joint (42).

2. The tunnel lining structure according to claim 1, characterized in that: The designed thickness δ of the corrosion-resistant energy-absorbing layer (2) is determined by the following method: A confined compression test is carried out on the corrosion-resistant energy-absorbing structure (21), a stress-strain curve of the energy-absorbing stage of the corrosion-resistant energy-absorbing structure (21) is obtained, and an energy absorption efficiency index η of the corrosion-resistant energy-absorbing structure (21) is determined, wherein the energy absorption stage includes an elastic stage and a pressure-yielding platform stage; the energy absorption efficiency index η is set to: η = ΔV / V = SΔL / SL = ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure (21), S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure (21), ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure (21), ε P is the end point strain of the yield plateau stage; Conduct tests on the surrounding rock of the tunnel to determine the long-term time-dependent deformation U of the surrounding rock. L The long-term aging deformation U L Set to: U L =U S +U C Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock; Determine the design thickness δ of the corrosion-resistant energy-absorbing layer (2); the design thickness δ of the corrosion-resistant energy-absorbing layer is set to: U A =U L -U R ; δ=U A / η; among them, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure (21), U R It is the reserved deformation amount of the secondary lining layer (4).

3. The tunnel lining structure according to claim 2, characterized in that: The porous ductile material (213) comprises polyurethane foam, polystyrene foam or foam rubber.

4. The tunnel lining structure according to claim 3, characterized in that: The polyethylene tube (211) has a diameter of 5-20 cm and a length of 1-6 m.

5. The tunnel lining structure according to claim 4, characterized in that: The back-sticking type diversion waterstop (51) is made of corrosion-resistant EPDM rubber.

6. The tunnel lining structure according to claim 5, characterized in that: The initial support layer (1) is filled with ultra-high performance concrete.

7. The tunnel lining structure according to claim 6, characterized in that: The secondary lining structure (41) is filled with ultra-high performance concrete.

8. The method for constructing a tunnel lining structure in a dilatant rheological or highly corrosive stratum according to any one of claims 1 to 7, wherein: The steps include: Filling the interior of a polyethylene tube (211) with a porous ductile material (213), and then hot-melt-sealing both ends of the polyethylene tube (211) with polyethylene hot-melt plugs (212) to obtain a corrosion-resistant energy-absorbing structure (21); Determine the design thickness δ of the corrosion-resistant energy-absorbing layer (2); After tunnel excavation, ultra-high performance concrete is sprayed onto the surrounding rock and support facilities are installed to form the initial support layer (1); After the initial support layer (1) is closed into a ring, a plurality of corrosion-resistant energy-absorbing structures (21) are positioned and installed on the initial support layer (1) to form the corrosion-resistant energy-absorbing layer (2); On the corrosion-resistant energy-absorbing layer (2), polymer flexible waterproof coiled materials are sequentially overlapped along the axial direction of the tunnel in the dilatant rheological or highly corrosive stratum to form a waterproof layer (3); Several drainage joints (5) and several secondary lining structures (41) are alternately installed in sequence along the axial direction of the tunnel. When the secondary lining structures (41) reach the construction strength requirements, the joints (42) between any two adjacent secondary lining structures (41) are filled with asphalt filling material to form a secondary lining layer (4).

9. The construction method according to claim 8, characterized in that: The method for determining the design thickness δ of the corrosion-resistant energy-absorbing layer (2) comprises: conducting a confined compression test on the corrosion-resistant energy-absorbing structure (21) to obtain a stress-strain curve of the energy-absorbing stage of the corrosion-resistant energy-absorbing structure (21), and determining an energy-absorbing efficiency index η of the corrosion-resistant energy-absorbing structure (21), wherein the energy-absorbing stage includes an elastic stage and a pressure-yielding platform stage; conducting a test on the surrounding rock of the tunnel to determine the long-term aging deformation U of the surrounding rock. L ; Determine the design thickness δ of the corrosion-resistant energy-absorbing layer (2); The energy absorption efficiency index η is set as: η=ΔV / V=SΔL / SL=ε P ; Wherein, ΔV is the volume compression at the end point of the pressure-releasing platform stage, V is the initial volume of the corrosion-resistant energy-absorbing structure (21), S is the cross-sectional area of ​​the corrosion-resistant energy-absorbing structure (21), ΔL is the length change at the end point of the pressure-releasing platform stage, L is the initial length of the corrosion-resistant energy-absorbing structure (21), and ε P is the end point strain of the yield plateau stage; The long-term aging deformation U L Set to: IN L =U S +U C ; The designed thickness δ of the corrosion-resistant energy-absorbing layer is set to: IN A =U L -IN R ; δ=U A / or; Among them, U S is the expansion deformation of the surrounding rock, U C is the rheological deformation of the surrounding rock, U A is the allowable deformation of the corrosion-resistant energy-absorbing structure (21), U R It is the reserved deformation amount of the secondary lining layer (4).

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