Inverted arch structure and construction method thereof

Abstract

The invention provides an inverted arch structure and a construction method thereof, and belongs to the technical field of tunnel inverted arch construction. The inverted arch structure comprises an arch body and a supporting mechanism, a plurality of sleeper grooves are symmetrically formed in the top face of the arch body, and steel rails are placed in the sleeper grooves so that a rail car installed on the steel rails can convey materials synchronously in the tunneling construction process; the supporting mechanisms are symmetrically arranged on the bottom side face of the arch body and located on the two sides of the tunnel extending direction, and the supporting mechanisms are suitable for adjusting the angle between the arch body and the steel arch frame so that the arch body can be matched with the main tunnel wall. The invention further provides a construction method of the inverted arch structure, the mode that the prefabricated inverted arch and the cast-in-place inverted arch are combined is adopted, the tunnel manufacturing cost can be remarkably reduced, the construction speed can be increased, the controllability of the construction quality is high, and the construction precision and efficiency can be improved easily.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel invert construction, and in particular to an invert structure and a construction method thereof. Background Art

[0002] In order to meet the needs of long tunnel construction, TBM horizontal guide auxiliary main tunnel construction is often used in modern road and bridge construction. The TBM method has the significant advantage of fast construction speed.

[0003] There are two main methods at present: one is to lay cast-in-place inverts and flat guide pavement together after all the flat guides in the main tunnel are penetrated to assist the construction of the main tunnel. The flat guide adopts fully cast-in-place inverts; the other is to use TBM flat guide while excavating and constructing prefabricated inverts to assist the construction of the main tunnel. Generally, in order to form a trackless transportation channel for auxiliary construction vehicles as soon as possible, a fully prefabricated invert structure is used.

[0004] However, although the first method of using fully cast-in-place inverts has a low overall cost, the construction quality is difficult to control. At the same time, in order to ensure the rapid transportation of materials in front of the TBM construction, a "steel stirrup" pavement structure is generally required in the tunnel, which will lead to inconvenience in walking in the tunnel and poor appearance conditions on the construction site; the on-site construction of the "steel stirrup" pavement is complicated, and the stirrups need to be removed during the later construction of the cast-in-place invert, which makes the construction process cumbersome and wasteful; and the cast-in-place invert cannot keep up with the construction of the heading face, which also causes the lining to not be closed in time. When encountering poor geological sections (such as large deformation, etc.), it will affect the safety of the structure.

[0005] The second method of using fully prefabricated inverts has a fast construction speed, but it is expensive, requires high installation precision, and has a slow construction speed. The fully prefabricated inverts need to be transported from outside the tunnel by trackless vehicles to the rail vehicles of the TBM excavation section for transportation, which greatly limits the speed and capacity of transportation.

[0006] In addition, neither method can synchronize the auxiliary construction of the main tunnel with the TBM's own construction, resulting in significant defects. Summary of the invention

[0007] In view of this, the present invention aims to solve the technical problems existing in two existing TBM tunnel construction technologies. A first object of the present invention is to provide an inverted arch structure, the inverted arch structure comprising: An arch body, wherein a plurality of rail sleeper grooves are symmetrically opened on the top surface of the arch body; rails are placed in the rail sleeper grooves so as to be suitable for rail vehicles installed on the rails to synchronously transport materials during the tunnel excavation construction process; The supporting mechanism is symmetrically arranged on the bottom side of the arch body and located on both sides of the tunnel extension direction. The supporting mechanism is suitable for adjusting the angle between the arch body and the steel arch frame so that the arch body fits with the main tunnel wall.

[0008] Furthermore, the supporting mechanism comprises: A support block, the curvature of the bottom surface of the support block is consistent with the curvature of the bottom surface of the arch body, and the bottom surface of the support block is flush with and fixed on the arch body; An adjustment mechanism is used to adjust the fit between the support block and the main hole wall.

[0009] Further, the adjustment mechanism includes: a screw, a first cushion block, a first jacket, a second cushion block and a locking nut; A cavity hole is formed downwardly on the top surface of the support block, a first cavity is formed at the upper end of the cavity hole and a second cavity is formed at the lower end, the first cavity and the second cavity are arranged concentrically with the cavity hole and form a limiting step, a first limiting groove is formed on the inner circumference of the first cavity, and a third limiting groove is formed on the inner circumference of the second cavity; The two ends of the screw are respectively provided with a first thread and a second thread; The first cushion block is provided with a first limiting key on its outer periphery and two second limiting grooves are symmetrically provided on its inner periphery; the first cushion block is adapted to fit into the first cavity, and the first limiting key matches with the first limiting groove; Two second limit keys are symmetrically arranged on the outer circumference of the first jacket, the first jacket is an inverted cone structure and a plurality of first clamping gaps are evenly opened on the circumference of the lower end, the first jacket is arranged in the first cushion block, the second limit keys are arranged in the second limit grooves, and the first jacket is made of elastic deformable material; Two third limit keys are symmetrically arranged on the outer circumference of the second cushion block, a threaded through hole is arranged in the second cushion block and the second thread of the screw rod is matched; the second cushion block is adapted to be in the second cavity, and the third limit key is matched with the third limit groove; The first thread of the screw rod passes through the locking nut, and the locking nut is arranged above the first jacket; when the locking nut is tightened, it contacts the top surface of the first jacket; The screw rod passes through the locking nut, the first jacket, the first cushion block, the cavity hole and the second cushion block in sequence from top to bottom.

[0010] Furthermore, a pry bar is detachably provided at the upper end of the screw rod, and a socket suitable for the pry bar is provided on the peripheral side of the locking nut.

[0011] Furthermore, it also includes a limit plate, which is symmetrically arranged on the top surface of the arch body and located at both ends perpendicular to the extension direction of the tunnel, and the limit plate is clamped in the steel arch frame.

[0012] Furthermore, a first groove is provided on the curved bottom surface of the arch body, and two ends of the first groove extend respectively to between the limit plates on the corresponding sides; a second groove is provided on the bottom surface of the support block and passes through the tunnel in a direction perpendicular to the extension direction, and the curvature and depth of the second groove are consistent with those of the first groove.

[0013] Furthermore, a third cavity is provided at the lower side of the support block, a clamping block is fitted in the third cavity, the top surface of the clamping block is rotatably connected to the lower end of the screw, and the notch provided at the lower end of the clamping block corresponds to the second groove.

[0014] Furthermore, a drainage groove is provided on the top surface of the arch body, the bottom of the drainage groove is lower than the bottom of the sleeper groove, the sleeper groove is connected from the bottom by a plurality of through-type first drainage holes, and the first drainage holes are connected to the drainage groove.

[0015] Furthermore, the arch body is symmetrically provided with through cavities along the extension direction of the tunnel, and a drainage ditch is arranged in the middle of the arch body; a second drainage hole is downwardly provided on the top surface of the arch body, and the second drainage hole is connected with the upper side of the drainage ditch; a plurality of through holes are downwardly provided on the top surface of the arch body, and the through holes are arranged between two of the sleeper grooves or between the sleeper groove and the drainage groove.

[0016] A second object of the present invention is to provide a construction method for an inverted arch structure. Based on the inverted arch structure described above, the construction method comprises the following steps: Step S1: hoisting the prefabricated arch body into the excavated main hole, and paving the arch body evenly at intervals on the invert arch base in the main hole; Step S2: after aligning the arch body, laying rails for material transportation in the sleeper grooves of the arch body; Step S3: adjusting the angle between the arch body and the steel arch frame through the supporting mechanism so that the arch body fits with the main cave wall; Step S4: making cast-in-place inverted arches between prefabricated arch bodies.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The above-mentioned design obtains an inverted arch structure. During construction, the prefabricated arches are evenly spaced on the inverted arch base in the excavated main tunnel. Steel rails are laid on the prefabricated arches to meet the material transportation needs of TBM construction. There is no need to transfer to rail transportation through trackless rubber-wheeled vehicles, so that the auxiliary construction of the main tunnel and the TBM itself can be synchronized. Support mechanisms are symmetrically set on the bottom side of the arch and on both sides of the tunnel extension direction, so that the support mechanisms can be used to adjust the angle between the arch and the steel arch frame to make the arch fit the main tunnel wall. Finally, cast-in-place inverted arches are used between the prefabricated arches. The use of prefabricated arches has fast construction speed and controllable quality. The cast-in-place inverted arches filled in the middle avoid the connection of the fully prefabricated inverted arches with the steel frame under the inverted arches one by one. The combination of the two can greatly reduce the construction difficulty and cost, and improve the construction speed and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 is a schematic diagram of a three-dimensional structure of an inverted arch structure provided in an embodiment of the present invention; Figure 2 A schematic diagram of an inverted arch structure provided in an embodiment of the present invention; Figure 3 A schematic diagram of an inverted arch structure from another viewing angle provided in an embodiment of the present invention; Figure 4 for Figure 2 A schematic diagram of the enlarged structure at A in the middle; Figure 5 A schematic diagram of the support mechanism structure provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the support block, the second cushion block, the clamping block and the second groove provided in an embodiment of the present invention; Figure 7 It is a schematic diagram of the exploded structure of the support mechanism provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the first cushion block and the first jacket provided in an embodiment of the present invention; Fig. 9 A schematic diagram of the structure of a second cushion block provided in an embodiment of the present invention; Fig.10 A schematic diagram of the support block structure provided in an embodiment of the present invention; Fig.11A schematic diagram of the structure of the second groove, the cavity hole, the second limiting groove and the third cavity provided in an embodiment of the present invention; Fig.12 A schematic diagram of the cross-sectional structure of a support block provided in an embodiment of the present invention.

[0020] Description of reference numerals: 10-arch body; 11-sleeper groove; 111-first drainage hole; 12-drainage groove; 13-through cavity; 14-drainage ditch; 141-second drainage hole; 15-through hole; 17-first groove; 20-limiting plate; 30- supporting mechanism; 31-support block; 311-second groove; 312-cavity hole; 313-first cavity; 3131-first limiting groove; 314-second cavity; 3141-third limiting groove; 315-third cavity; 32-adjusting mechanism; 321-screw rod; 3211-first thread; 3212-second thread; 3213-pry bar; 322-first jacket; 3221-second limit key; 3222-first clamping gap; 323-first cushion block; 3231-first limit key; 3232-second limit groove; 324-second cushion block; 3241-third limit key; 325-locking nut; 3251-jack; 33-Card block. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In the description of this specification, the description with reference to the terms "embodiment", "one embodiment" and "one implementation method" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or implementation method are included in at least one embodiment or implementation method of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or implementation method. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or implementation methods in a suitable manner. Based on the implementation methods in the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] See also Figure 1-12 As shown, an embodiment of the present invention provides an inverted arch structure, which includes an arch body 10 and a supporting mechanism 30, wherein: The top surface of the arch body 10 is symmetrically provided with a plurality of sleeper grooves 11 along the tunnel excavation direction. Rails are placed in the sleeper grooves 11, and rail cars are installed on the rails. In this way, during the tunnel excavation construction process, materials can be synchronously transported outwards by the rail cars on the rails.

[0025] The support mechanism 30 is symmetrically arranged on the bottom side of the arch body 10, and the support mechanism 30 is located on both sides of the tunnel extension direction of the arch body 10, so that the support mechanism 30 can be used to adjust the angle between the arch body 10 and the steel arch frame to make the arch body 10 fit with the main tunnel wall.

[0026] Specifically, during construction, the prefabricated arch bodies 10 are evenly spaced and arranged on the base of the invert in the excavated main tunnel. After the prefabricated arch bodies 10 are erected, the fit between the arch bodies 10 and the main tunnel wall is adjusted by the supporting mechanism 30. A sleeper groove 11 is opened on the prefabricated arch body 10, and rails are laid on the sleeper groove 11 to meet the material transportation needs during the TBM construction process. In this way, there is no need to transfer to rail transportation through a trackless rubber-tyred vehicle, and the auxiliary construction of the main tunnel and the TBM itself can be synchronized.

[0027] It should be explained that TBM (abbreviation of Tunnel Boring Machine) is a large-scale engineering machinery equipment specially used for tunnel excavation in rock formations. It integrates mechanical, electronic, hydraulic, laser, control and other technologies, and can realize parallel and continuous operation of construction processes such as excavation, support, and slag discharge.

[0028] As a preferred embodiment of the present invention, the number of sleeper grooves 11 is set to two. Of course, the number and position of the sleeper grooves 11 can be adaptively adjusted according to actual construction conditions. This application does not make any restrictive description on the number and position of the sleeper grooves 11.

[0029] Specifically, see Figure 7 As shown, in one embodiment of the present invention, the support mechanism 30 includes a support block 31 and an adjustment mechanism 32, wherein: The curvature of the bottom surface of the support block 31 is consistent with the curvature of the bottom surface of the arch body 10 , and the bottom surface of the support block 31 is flush with and fixed on the arch body 10 .

[0030] The adjustment mechanism 32 is used to adjust the fit between the support block 31 and the main hole wall (not shown in the drawings).

[0031] Therefore, since the curvature of the bottom surface of the support block 31 is consistent with the curvature of the bottom surface of the arch body 10, the support block 31 and the arch body 10 are kept consistent in fit with the main cave wall; the adjustment mechanism 32 is used to adjust the angle of the support block 31, and the adjustment mechanism 32 in this embodiment can be extended and fixed relative to the support block 31.

[0032] It is understandable that any guide rail structure, screw structure, jack structure or the like that can achieve similar functions can be used as the adjustment mechanism 32 .

[0033] See also Figure 5-Figure 12 As shown, in one embodiment of the present invention, the adjustment mechanism 32 includes a screw 321, a first jacket 322, a first cushion block 323, a second cushion block 324 and a locking nut 325, wherein: The two ends of the screw rod 321 are respectively provided with a first thread 3211 and a second thread 3212 .

[0034] A cavity 312 is formed on the top surface of the support block 31 and extends downward therethrough. A first cavity 313 is formed at the upper end of the cavity 312 and a second cavity 314 is formed at the lower end. The first cavity 313 and the second cavity 314 are arranged concentrically with the cavity 312 and form a limiting step. A first limiting groove 3131 is formed on the inner periphery of the first cavity 313 and a third limiting groove 3141 is formed on the inner periphery of the second cavity 314.

[0035] A first limiting key 3231 is disposed on the outer periphery of the first cushion block 323 and two second limiting grooves 3232 are symmetrically provided on the inner periphery; the first cushion block 323 is adapted to fit into the first cavity 313 , and the first limiting key 3231 matches with the first limiting groove 3131 .

[0036] Two second limit keys 3221 are symmetrically arranged on the outer circumference of the first jacket 322. In this embodiment, the first jacket 322 is preferably arranged as an inverted cone structure, and a plurality of first clamping gaps 3222 are evenly opened on the lower end circumference. The first jacket 322 is arranged in the first cushion block 323, and the second limit key 3221 is arranged in the second limit groove 3232. It can be understood that the first jacket 322 is made of elastically deformable material.

[0037] Two third limit keys 3241 are symmetrically arranged on the outer circumference of the second cushion block 324, a threaded through hole is arranged inside the second cushion block 324 and the second thread 3212 of the screw rod 321 cooperates; the second cushion block 324 is adapted to the second cavity 314, and the third limit key 3241 cooperates with the third limit groove 3141.

[0038] The first thread 3211 of the screw rod 321 passes through the locking nut 325, and the locking nut 325 is arranged above the first jacket 322; when the locking nut 325 is tightened, it contacts the top surface of the first jacket 322; The screw rod 321 passes through the locking nut 325 , the first jacket 322 , the first cushion block 323 , the cavity hole 312 and the second cushion block 324 in sequence from top to bottom.

[0039] Specifically, since the screw rod 321 passes through the locking nut 325, the first sleeve 322, the first cushion block 323, the cavity hole 312 of the support block 31 and the second cushion block 324 from top to bottom in sequence, the entire adjustment mechanism 32 can be installed on the support block 31; wherein the first limit key 3231 arranged on the outer periphery of the first cushion block 323 is adapted in shape to the first limit groove 3131 arranged on the inner periphery of the first cavity 313, and when the first limit key 3231 is inserted into the first limit groove 3131, the first cushion block 323 can be limited in the direction of rotation around the axis in the first cavity 313, and in addition, the first cavity 313 and the cavity hole 312 are concentric circular holes, and the inner diameter of the first cavity 313 is larger than the inner diameter of the cavity hole 312, so that a limit step is formed at the junction of the first cavity 313 and the cavity hole 312, and the limit step can vertically limit the first cushion block 323.

[0040] Therefore, through the action of the second limit groove 3232 and the second limit key 3221, the first sleeve 322 is restricted from rotating around the axis, so that in the process of adjusting the fit of the arch body 10, the first cushion block 323 and the first sleeve 322 do not rotate with the screw 321, and the screw 321 is prevented from continuing to rotate after clamping, causing the adjustment mechanism 32 to loosen.

[0041] In addition, since the first jacket 322 is an inverted cone structure, and a plurality of first clamping gaps 3222 are evenly opened on the circumferential side of the lower end of the first jacket 322, and the first clamping gaps 3222 and the second limit keys 3221 are evenly spaced, when the locking nut 325 is tightened, the first jacket 322 is deformed due to the downward squeezing of the conical outer periphery to clamp the screw 321.

[0042] Similarly, two third limit keys 3241 are symmetrically arranged on the outer circumference of the second cushion block 324, and the second thread 3212 of the screw 321 cooperates with the threaded through hole of the second cushion block 324, and the third limit key 3241 arranged on the outer periphery of the second cushion block 324 is adapted in shape to the third limit groove 3141 arranged on the inner periphery of the second cavity 314, thereby realizing the telescopic adjustment of the screw 321.

[0043] The second cavity 314 opened at the lower end of the cavity hole 312 is adapted to the shape of the second cushion block 324, and the third limiting groove 3141 arranged on the inner periphery of the second cavity 314 is adapted to the shape of the third limiting key 3241. Due to the cooperation between the third limiting groove 3141 and the third limiting key 3241, the second cushion block 324 is fixed during the rotation adjustment process, making the rotation adjustment more effective.

[0044] In some other embodiments, the cross-sections of the first cushion block 323 and the second cushion block 324 may also be square, circular or other shapes.

[0045] like Figure 7 As shown, in another embodiment of the present invention, a pry bar 3213 is detachably provided at the upper end of the screw rod 321 , and a socket 3251 suitable for the pry bar 3213 is provided on the peripheral side of the locking nut 325 .

[0046] Therefore, a pry bar 3213 is separately provided at the upper end of the screw rod 321 , which can not only increase the force arm to rotate the screw rod 321 , but also be used for tightening the locking nut 325 .

[0047] See also Figure 3 , 4 As shown, in one embodiment of the present invention, the inverted arch structure further includes a limit plate 20, which is symmetrically arranged on the top surface of the arch body 10 and located at both ends perpendicular to the extension direction of the tunnel, and the limit plate 20 is clamped in the steel arch frame.

[0048] As a preferred mode of this embodiment, the limiting plates 20 are symmetrically arranged in pairs at the two ends of the upper side of the arch body 10, so that the two ends of the arch body 10 can be aligned with the connecting plates at the connection of the steel arch frame of the side wall and the invert arch.

[0049] See also Figure 2 and Figure 6 As shown, in another embodiment of the present invention, a first groove 17 is provided on the arc-shaped bottom surface of the arch body 10, and both ends of the first groove 17 extend to between the corresponding side limit plates 20 respectively; and a second groove 311 is provided on the bottom side surface of the support block 31 and passes through the tunnel in a direction perpendicular to the extension direction, and the curvature and depth of the second groove 311 are consistent with those of the first groove 17.

[0050] The advantage of this arrangement is that the limiting plate 20 facilitates the fit and limiting of the first groove 17 and the main tunnel steel arch frame. When the steel arch frame is placed in the first groove 17, the outer arc side of the arch body 10 can fit the main tunnel inverted arch wall and the steel arch frame, which is convenient for secondary lining construction.

[0051] It can be understood that, in the present embodiment, the number of the first grooves 17 is set to one, and in some other embodiments, the number of the first grooves 17 can also be set correspondingly according to the number of steel arch frames spanned by the arch body 10 during construction.

[0052] See also Figure 7 , 11 As shown in Figures 12, in one embodiment of the present invention, a third cavity 315 is provided on the lower surface of the support block 31, and a clamping block 33 is fitted in the third cavity 315. The top surface of the clamping block 33 is rotatably connected to the lower end of the screw rod 321, and the notch provided on the bottom end surface of the clamping block 33 corresponds to the second groove 311.

[0053] During the implementation process, since the block 33 is rotatably connected to the screw rod 321, when the screw rod 321 is rotated, the block 33 is driven to move in the third cavity 315, so that the block 33 is pressed against the steel arch frame, and the notch opened at the lower end of the block 33 corresponds to the second groove 311, so that the block 33 can be engaged on the steel arch frame, which makes the arch body 10 more stable when adjusted.

[0054] See also Figure 3 , Figure 4 As shown, in one embodiment of the present invention, a drainage groove 12 is opened on the top surface of the arch body 10, and the depth of the drainage groove 12 is greater than the depth of the sleeper groove 11. Each sleeper groove 11 is connected from the bottom by a plurality of through-type first drainage holes 111, and the first drainage holes 111 are also connected to the drainage groove 12.

[0055] Therefore, since the first drainage hole 111 communicates with the bottom of the sleeper groove 11 and the drainage groove 12 , and the depth of the drainage groove 12 is greater than the depth of the sleeper groove 11 , drainage of the sleeper groove 11 is facilitated.

[0056] See also Figure 3 , Figure 4 As shown, in one embodiment of the present invention, through cavities 13 are symmetrically opened on the arch body 10 along the extension direction of the tunnel. The arrangement of the through cavities 13 can make the arch body 10 lightweight while ensuring the strength of the arch body 10, so as to facilitate lifting and paving.

[0057] Preferably, the through cavity 13 in this embodiment is set to a semi-arched structure. In some other embodiments, the cross-sectional shape of the through cavity 13 can also be set to a circular, square, elliptical, etc. This embodiment does not impose any restrictions on the shape of the through cavity 13, and specifically meets the requirements of lightweight arches. In addition, the number of through cavities 13 can also be adjusted according to actual needs.

[0058] In one embodiment of the present invention, a drainage ditch 14 is disposed in the middle of the arch body 10 , and a second drainage hole 141 is opened downward on the top surface of the arch body 10 , and the second drainage hole 141 is communicated with the drainage ditch 14 .

[0059] Therefore, by setting a drainage ditch 14 in the middle of the arch body 10 along the extension direction of the tunnel, preferably the drainage ditch 14 is set between the two through cavities 13 close to the center of the arch body 10, and a second drainage hole 141 is opened on the upper side of the drainage ditch 14. The drainage ditch 14 is connected to the upper side of the arch body 10 through the second drainage hole 141. The second drainage hole 141 can be used to insert a drainage pipe, so that the drainage ditch 14 can be used for drainage of the main hole.

[0060] It is understandable that one or more second drainage holes 141 may be provided on a single arch body 10 according to drainage requirements, and this embodiment does not impose any limitation on the number of the second drainage holes 141 .

[0061] See also Figure 3 , Figure 4 As shown, in one embodiment of the present invention, a plurality of through holes 15 are opened downward on the top surface of the arch body 10, and the through holes 15 are located between two sleeper grooves 11 or between the sleeper groove 11 and the drainage groove 12. The through holes 15 are used to connect the through cavity 13, which can be used for grouting and vibration during construction. This makes it convenient to fill the through cavity 13 when filling the inverted arch, thereby completing the overall inverted arch filling construction. It should be noted that the through holes 15 should be set away from the sleeper grooves 11 and the drainage grooves 12.

[0062] See also Figure 3 , Figure 4 As shown, in one embodiment of the present invention, the outer contour of the limiting plate 20 is an arc-shaped structure, which can adapt to the curvature of the side wall.

[0063] The specific working process of the inverted arch structure is as follows: During construction, the prefabricated arches 10 are evenly spaced and arranged on the invert base in the excavated main tunnel, and rails are laid on the prefabricated arches 10 to meet the material transportation requirements of TBM construction.

[0064] The sleeper groove 11 drains water through the first drainage hole 111 and the drainage groove 12. The through cavity 13 can make the arch body 10 lightweight while ensuring the strength of the arch body 10 to facilitate lifting and paving. The second drainage hole 141 can be used to insert the drainage pipe, the drainage ditch 14 can be used for the main hole to drain water, and the through hole 15 can be used for grouting and vibration, so that the through cavity 13 can be filled together when filling the invert, completing the overall invert filling construction.

[0065] By adjusting the fit between the supporting mechanism 30 and the steel arch frame, and when fine-tuning the fit between the arch body 10 and the steel arch frame and the main cave wall, the locking nut 325 can be loosened upward to a certain extent first, and the screw 321 can be rotated by the crowbar 3213 to drive the block 33 to move in the third cavity 315 so that it is pressed against the steel arch frame. The notch on the outside of the block 33 can be engaged with the steel arch frame, and the limiting structures (the first limiting key 3231, the first limiting groove 3131, the second limiting groove 3232, the second limiting key 3221, the third limiting key 3241 and the third limiting groove 3141) arranged on the first cushion block 323, the first jacket 322 and the second cushion block 324 can prevent the screw 321 from rotating.

[0066] After the adjustment is completed, remove the crowbar 3213 from the top of the screw rod 321 and insert it into the socket 3251 around the locking nut 325, rotate and tighten the locking nut 325, and press the first sleeve 322 against the first cushion block 323 and against the first cavity 313. At the same time, the first sleeve 322 will be tightened under pressure due to the existence of the first clamping gap 3222, thereby locking the screw rod 321 to prevent it from loosening and rotating, so that the block 33 can be stably pressed against the steel arch frame, so as to achieve the purpose of fine-tuning the fit of the arch body 10 on the steel arch frame and the main cave invert wall through the support block 31.

[0067] This inverted arch structure is beneficial to the overall structural stability of the arch body 10 after paving, thereby ensuring the overall stability of the main tunnel inverted arch structure and facilitating the secondary lining construction; cast-in-place inverted arches are used between the prefabricated arch bodies 10. The use of prefabricated arch bodies 10 has a fast construction speed and controllable quality. The cast-in-place inverted arch filled in the middle avoids the one-by-one connection of the fully prefabricated inverted arch and the steel frame under the inverted arch. The combination of the two can greatly reduce the construction difficulty and cost, and improve the construction speed and accuracy.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An inverted arch structure, characterized in that: include: An arch body (10), wherein a plurality of rail sleeper grooves (11) are symmetrically formed on the top surface of the arch body (10); rails are placed in the rail sleeper grooves (11) so as to be suitable for a rail vehicle mounted on the rails to synchronously transport materials during tunnel excavation construction; A support mechanism (30), the support mechanism (30) being symmetrically arranged on the bottom side of the arch body (10) and located on both sides of the tunnel extension direction, the support mechanism (30) being suitable for adjusting the angle between the arch body (10) and the steel arch frame so that the arch body (10) fits with the main tunnel wall.

2. The inverted arch structure according to claim 1, characterized in that: The supporting mechanism (30) comprises: A support block (31), wherein the curvature of the bottom surface of the support block (31) is consistent with the curvature of the bottom surface of the arch body (10), and the bottom surface is flush with and fixed on the arch body (10); An adjustment mechanism (32), wherein the adjustment mechanism (32) is used to adjust the degree of fit between the support block (31) and the main hole wall.

3. The inverted arch structure according to claim 2, characterized in that: The adjustment mechanism (32) comprises: a screw rod (321), a first cushion block (323), a first jacket (322), a second cushion block (324), and a locking nut (325); A cavity (312) is provided on the top surface of the support block (31) and extends downward therethrough; a first cavity (313) is provided at the upper end of the cavity (312) and a second cavity (314) is provided at the lower end; the first cavity (313) and the second cavity (314) are arranged concentrically with the cavity (312) and form a limiting step; a first limiting groove (3131) is provided on the inner periphery of the first cavity (313) and a third limiting groove (3141) is provided on the inner periphery of the second cavity (314); The two ends of the screw rod (321) are respectively provided with a first thread (3211) and a second thread (3212); The first cushion block (323) is provided with a first limiting key (3231) on its outer periphery and two second limiting grooves (3232) are symmetrically provided on its inner periphery; the first cushion block (323) is adapted to fit into the first cavity (313), and the first limiting key (3231) matches with the first limiting groove (3131); Two second limit keys (3221) are symmetrically arranged on the outer circumference of the first jacket (322); the first jacket (322) is an inverted cone structure and a plurality of first clamping gaps (3222) are evenly arranged on the circumference of the lower end; the first jacket (322) is arranged in the first cushion block (323); the second limit keys (3221) are arranged in the second limit grooves (3232); and the first jacket (322) is made of an elastic deformable material; Two third limit keys (3241) are symmetrically arranged on the outer circumference of the second cushion block (324); a threaded through hole is arranged inside the second cushion block (324) and the second thread (3212) of the screw rod (321) cooperates; the second cushion block (324) is adapted to fit into the second cavity (314), and the third limit keys (3241) cooperate with the third limit groove (3141); The first thread (3211) of the screw rod (321) passes through the locking nut (325), and the locking nut (325) is arranged above the first jacket (322); when the locking nut (325) is tightened, it contacts the top surface of the first jacket (322); The screw rod (321) passes through the locking nut (325), the first jacket (322), the first cushion block (323), the cavity hole (312), and the second cushion block (324) in sequence from top to bottom.

4. The inverted arch structure according to claim 3, characterized in that: A pry bar (3213) is detachably provided at the upper end of the screw rod (321), and a plug hole (3251) suitable for the pry bar (3213) is provided on the peripheral side of the locking nut (325).

5. The inverted arch structure according to claim 3, characterized in that: It also comprises a limit plate (20), the limit plate (20) being symmetrically arranged on the top surface of the arch body (10) and located at two ends perpendicular to the tunnel extension direction, and the limit plate (20) being clamped in the steel arch frame.

6. The inverted arch structure according to claim 5, characterized in that: The arc-shaped bottom surface of the arch body (10) is provided with a first groove (17), and the two ends of the first groove (17) respectively extend to between the limit plates (20) on the corresponding sides; the bottom surface of the support block (31) is provided with a second groove (311) penetrating in a direction perpendicular to the extension direction of the tunnel, and the second groove (311) and the first groove (17) have the same arc and depth.

7. The inverted arch structure according to claim 6, characterized in that: A third cavity (315) is provided at the lower side of the support block (31), a clamping block (33) is arranged in the third cavity (315), the top surface of the clamping block (33) is rotatably connected to the lower end of the screw rod (321), and a notch provided at the lower end of the clamping block (33) and the second groove (311) are arranged correspondingly.

8. The inverted arch structure according to claim 1, characterized in that: The top surface of the arch body (10) is provided with a drainage groove (12), the bottom of the drainage groove (12) is lower than the bottom of the sleeper groove (11), the sleeper groove (11) is connected from the bottom by a plurality of through-type first drainage holes (111), and the first drainage holes (111) are connected to the drainage groove (12).

9. The inverted arch structure according to claim 8, characterized in that: The arch body (10) is provided with through cavities (13) symmetrically along the tunnel extension direction, and a drainage ditch (14) is provided in the middle of the arch body (10); a second drainage hole (141) is provided downwardly on the top surface of the arch body (10), and the second drainage hole (141) is communicated with the upper side of the drainage ditch (14); and a plurality of through holes (15) are provided downwardly on the top surface of the arch body (10), and the through holes (15) are provided between two of the sleeper grooves (11) or between the sleeper groove (11) and the drainage ditch (12).

10. A construction method of an inverted arch structure, based on the inverted arch structure according to any one of claims 1 to 9, characterized in that: The construction method comprises the steps of Step S1: hoisting the prefabricated arch body (10) into the excavated main tunnel, and paving the arch body (10) at even intervals on the invert base in the main tunnel; Step S2: after the arch body (10) is accurately aligned, a steel rail for material transportation is laid in the rail sleeper groove (11) of the arch body (10); Step S3: adjusting the angle between the arch body (10) and the steel arch frame by means of the support mechanism (30) so that the arch body (10) fits in with the main cave wall; Step S4: making a cast-in-place inverted arch between the prefabricated arch bodies (10).

Images