A storage ring tunnel sawtooth wall crack control template structure and construction method

Abstract

The present application relates to the technical field of tunnel construction, and specifically to a template structure and construction method for controlling cracks in a zigzag wall of a storage ring tunnel, comprising a support template and a prestressed anchor, wherein the support template comprises a pre-tensioning template and a post-tensioning template; a steel cage is provided in both the pre-tensioning template and the post-tensioning template; the pre-tensioning template and the post-tensioning template are both in an "L" shape, and a plurality of pre-tensioning templates and post-tensioning templates are connected end to end to form a template for the zigzag wall of the storage ring tunnel; two partitions are provided in the post-tensioning template, and an induced joint is formed between the two partitions; the template structure is provided, and an induced joint is provided on the post-tensioning template, and the wall of the pre-tensioning long side template section is prestressed, so that the induced joint tends to expand to release the stress of the pre-tensioning wall section, and then after the induced joint is cast, the wall of the post-tensioning long side template is prestressed, so as to facilitate crack control of the zigzag wall as a whole and improve the rigidity and crack resistance of the wall.

Description

Technical Field

[0001] The present application relates to the technical field of tunnel construction, and in particular to a storage ring tunnel sawtooth wall crack control template structure and a construction method. Background Art

[0002] The storage ring tunnel is the core of a high-energy synchrotron radiation source project and the most important component for conducting scientific research. It is a ring-shaped structure used to house and maintain the stable operation of high-energy particle or electron beams. It provides a closed environment, ensuring that the particle beams can carry out experimental processes such as acceleration, collision, and synchrotron radiation generation without external interference. Storage ring tunnels typically have specific geometries and dimensions to suit the needs of different experiments.

[0003] The periphery of the storage ring tunnel is usually surrounded by multiple sections of serrated walls, which form a circular area. The storage ring tunnel is located on the inner side of the multiple sections of serrated walls. The serrated walls are "L"-shaped, and each section of the serrated wall includes a long wall and a short wall. The long wall and the short wall are arranged vertically to allow high-energy particles to collide and move in the tunnel surrounded by the serrated walls.

[0004] During the construction of the storage ring, multiple sections of serrated walls were cast in sections and finally connected into a whole. Due to the long circumference of the storage ring tunnel and the large span of the long wall of the serrated wall, cracks are prone to occur on the side walls of the long wall, affecting the normal progress of scientific research experiments. Summary of the Invention

[0005] In order to control the cracking risk of the serrated wall, the present application provides a storage ring tunnel serrated wall crack control template structure and construction method.

[0006] The present application provides a storage ring tunnel sawtooth wall crack control template structure and construction method using the following technical solutions:

[0007] A storage ring tunnel sawtooth wall crack control formwork structure includes a support formwork and prestressed anchors. The support formwork includes a pre-tensioning formwork and a post-tensioning formwork. Reinforcement cages are provided in both the pre-tensioning formwork and the post-tensioning formwork. The pre-tensioning formwork and the post-tensioning formwork are both L-shaped. Multiple pre-tensioning formworks and post-tensioning formworks are spaced apart and connected end-to-end to form a storage ring tunnel sawtooth wall formwork.

[0008] The pre-tensioned formwork includes a pre-tensioned long side formwork section and a pre-tensioned short side formwork section, and the post-tensioned formwork includes a post-tensioned long side formwork section and a post-tensioned short side formwork section; one end of the pre-tensioned long side formwork section is connected to the pre-tensioned short side formwork section, and the other end is connected to the post-tensioned short side formwork section; a plurality of prestressed anchors are respectively arranged in the pre-tensioned long side formwork section and the post-tensioned long side formwork section, and the prestressed anchors are fixedly connected to the steel cage mesh;

[0009] Two partitions are arranged in the post-tensioning template, the two partitions are arranged in parallel, and an induced seam is formed between the two partitions.

[0010] By adopting the above technical solution, the template structure is set up, and an induced joint is set on the post-tensioned elongated side template section. When the serrated wall of the storage ring is constructed, the supporting template is cast and constructed, and the wall of the first-tensioned elongated side template section is prestressed after casting, so that the wall of the first-tensioned elongated side template section shrinks. At the same time, during the tensioning, the induced joint in the post-tensioned elongated side template section tends to expand, and the stress inside the wall of the first-tensioned elongated side template section is released from the position of the induced joint; after the wall of the first-tensioned elongated side template section is tensioned, the induced joint is cast, and then the wall of the post-tensioned elongated side template section is tensioned, so that the wall of the post-tensioned elongated side template section shrinks, so as to avoid cracks in the serrated wall and improve the rigidity of the serrated wall and the overall crack resistance.

[0011] In a specific embodiment, the prestressed anchor comprises a prestressed steel strand, a fixed end anchor assembly and a tension end anchor assembly;

[0012] The fixed end anchor assembly and the tensioning end anchor assembly are respectively arranged at both ends of the length direction of the prestressed steel strand; the prestressed steel strand is fixedly arranged on the steel cage net, and the extension direction of the prestressed steel strand is parallel to the length direction of the pre-tensioned long side template section or the post-tensioned long side template section;

[0013] The fixed-end anchor assembly includes an extruded anchor head, a fixed-end pressure plate, and a fixed-end spiral rib; the extruded anchor head is coaxially fixedly connected to one end of the prestressed steel strand, the fixed-end pressure plate and the fixed-end spiral rib are both sleeved on the prestressed steel strand, the fixed-end pressure plate is located between the extruded anchor head and the fixed-end spiral rib, and both side walls of the fixed-end pressure plate are connected to the extruded anchor head and the fixed-end spiral rib respectively;

[0014] The tensioning end anchor assembly includes a tensioning end spiral rib, a tensioning end pressure plate, a cavity mold and a tensioning anchor; the tensioning end spiral rib, the tensioning end pressure plate and the cavity mold are all sleeved on the prestressed steel strand, the tensioning end pressure plate is located between the tensioning end spiral rib and the cavity mold, one end of the tensioning end pressure plate is fixedly connected to the tensioning end spiral rib, and the other end abuts against the cavity mold; one end of the cavity mold away from the tensioning end pressure plate abuts against the end template of the first tensioning long side template section or the second tensioning long side template section; the tensioning anchor is arranged in the inner cavity of the cavity mold;

[0015] The prestressed steel strand passes through the end formwork of the pre-tensioned long side formwork section or the post-tensioned long side formwork section close to the tensioning end anchor assembly.

[0016] By adopting the above technical solution, the prestressed anchor is set up, and when prestressed tensioning is carried out, the prestressed steel strand and the fixed end anchor assembly are buried in the poured concrete, and the fixed end pressure plate supports the extrusion anchor head to prevent the prestressed steel strand from driving the extrusion anchor head to move in the concrete when the prestressed steel strand is subjected to force, thereby affecting the quality of tensioning; at the same time, the tensioning end anchor assembly, the tensioning end spiral reinforcement, the hole mold and the tensioning end pressure plate are all buried in the concrete wall, and the hole mold provides an installation space for the tensioning anchor. During tensioning, force is applied to one end of the prestressed steel strand passing through the hole mold, and the tensioning anchor squeezes the hole mold and the tensioning end pressure plate, and the tensioning end pressure plate supports the tensioning anchor and the hole mold, so as to avoid damage to the concrete wall.

[0017] In a specific possible implementation scheme, the tensioning end anchor assembly also includes a clip, an anchor hole is provided on the tensioning anchor, the clip is engaged in the anchor hole, the tensioning anchor is embedded in the inner cavity of the cavity mold, and the prestressed steel strand extends out of the cavity mold at one end and passes through the clip; the end of the clip is flush with the side wall of the tensioning anchor, and the end of the prestressed steel strand away from the fixed end anchor assembly is provided with a tensioning jack, and the end face of the tensioning jack is in contact with the end face of the tensioning anchor away from the tensioning end pressure plate.

[0018] By adopting the above technical solution, the clip is engaged in the anchor hole, and the prestressed steel strand is passed through the clip. The tensioning jack applies force to the prestressed steel strand, causing the prestressed steel strand to stretch. The clip limits the movement direction of the prestressed steel strand, thereby preventing the prestressed steel strand from shrinking and improving the quality of prestressed stretching.

[0019] In a specific possible implementation scheme, the support formwork further includes diagonal braces, and a plurality of the diagonal braces are respectively arranged on both sides of the support formwork.

[0020] By adopting the above technical solution, the inclined braces are provided to support the side walls of the support formwork that are away from each other. When pouring the wall, it is convenient to prevent the support formwork from tilting to one side as a whole, thereby affecting the verticality of the wall.

[0021] In a specific feasible implementation scheme, the support formwork also includes an operating platform and a plurality of support rods. The operating platform is fixedly arranged on the top wall of the support formwork, and one end of the support rod is fixedly connected to the outer wall of the support formwork, and the other end is fixedly connected to the bottom wall of the operating platform. The plurality of support rods are evenly distributed along the length direction of the operating platform.

[0022] By adopting the above technical solution, the operating platform is set up, which makes it convenient to set up equipment and tools on the operating platform during wall pouring construction. At the same time, it is also convenient for operators to observe the quality and progress of construction through the operating platform.

[0023] A construction method for a zigzag wall crack control template structure for a storage ring tunnel comprises the following steps:

[0024] S1. Measure and mark, determine the construction position of the storage ring serrated wall according to the design drawings, reserve the induced joint, and determine the construction position of the serrated wall on both sides of the induced joint;

[0025] S2. Binding and welding of steel cages within the construction area of ​​the sawtooth wall;

[0026] S3. Install prestressed anchors on the steel cage;

[0027] S4. Set up support formwork and operating platform around the steel cage;

[0028] S5, concrete pouring;

[0029] S6. Prestressing the wall of the multiple pre-tensioned long side formwork sections multiple times;

[0030] S7. Remove the support formwork and operating platform and backfill the induced joints with grouting;

[0031] S8. Prestress the walls of multiple sections of post-tensioned long side formwork sections respectively; the overall construction of the storage ring serrated wall is completed.

[0032] By adopting the above technical solution, the casting position of the storage ring serrated wall is first measured and marked to determine the construction position of the serrated wall and the reserved position of the induced joint. Then, according to the design requirements, the steel cage is tied and welded in the marked area of ​​the serrated wall. Then, prestressed anchors are installed on the steel cage to provide preliminary preparation for prestressing. Then, support formwork and operating platform are installed on the side of the steel cage, and partitions are installed in the post-tensioning long side formwork section to form an induced joint. Then, the support formwork is provided through the operating platform. Concrete is poured in the cavity of the plate to form a zigzag wall. After the concrete solidifies and takes shape, the wall of the pre-tensioned long side formwork section is prestressed to make the wall of the pre-tensioned long side formwork section shrink. In the same way, multiple sections of the wall of the pre-tensioned long side formwork section are constructed, the supporting formwork and the operating platform are removed, the induced joints are poured, and finally the wall of the multiple sections of the post-tensioned long side formwork section is tensioned to make the wall of the post-tensioned long side formwork section shrink, thereby improving the rigidity of the zigzag wall and the overall crack resistance.

[0033] In a specific embodiment, the S6 comprises the following steps:

[0034] S61. After the concrete strength reaches 40%, remove the end formwork of the pre-tensioned long side formwork section close to the tensioning end, and perform the first tensioning on the wall of the pre-tensioned long side formwork section, maintaining the tensioning control stress at 50% of the design stress;

[0035] S62. After the concrete strength reaches 80%, the wall of the pre-tensioned long side formwork section is tensioned for the second time, and the tensioning control stress is maintained at 110% of the design stress;

[0036] S63. Remove the tensioning jacks and cut off the excess prestressed steel strands;

[0037] S64, sealing the anchor: injecting concrete into the cavity mold to seal the prestressed steel strand;

[0038] S65. Repeat steps S61-S64 to prestress the walls of multiple sections of pre-tensioned long-side formwork.

[0039] By adopting the above technical solution, tensioning is carried out when the concrete strength of the wall is 40% and 80% respectively, so as to ensure that the tensioning of the prestressed steel strands meets the design requirements, thereby improving the tensioning quality and overall stability of the wall.

[0040] In a specific embodiment, the S61 includes the following steps:

[0041] S611. Use testing equipment to test the concrete wall. When the concrete strength reaches 40%, remove the end formwork of the pre-tensioned long side formwork segment close to the tensioning end anchor assembly, and pull out the plastic plug mold of the cavity mold to expose the cavity mold cavity.

[0042] S612. Clean the concrete and debris from the cavity of the mold, insert the tension anchor into the cavity of the mold, and position the prestressed steel strand in the anchor hole of the tension anchor. Then, place the clip over the prestressed steel strand and move the clip so that the clip engages in the anchor hole and the end face of the clip is flush with the end face of the tension anchor.

[0043] S613. Sleeve a tensioning jack over the prestressed steel strand, with the end of the tensioning jack abutting against the side wall of the tensioning anchor. Connect a hydraulic drive device to the tensioning jack, and adjust the hydraulic drive device so that the tensioning jack applies 10% of the design stress. The tensioning jack pulls the prestressed steel strand to extend. After holding the load for 2 minutes, increase the force applied by the tensioning jack to 20% of the design stress. Hold the load again for 2 minutes, then increase the force applied by the tensioning jack to 50% of the design stress. After holding the load for 2 minutes, unload the load to zero.

[0044] S614. Remove the tensioning jack and temporarily cover the cavity mold and the prestressed tensioning end working surface.

[0045] By adopting the above technical solution, during the first tensioning, tension is applied to the prestressed steel strands in stages, and the local loads of the prestressed steel strands and the serrated wall are slowly changed, thereby avoiding damage to the steel strands and the serrated wall.

[0046] In a specific embodiment, the S62 includes the following steps:

[0047] S621. Use testing equipment to test the concrete wall. Once the concrete strength reaches 80%, remove the temporary cover on the prestressed tension end working surface.

[0048] S622. Reinstall the tensioning jack and hydraulic drive device; adjust the hydraulic drive device so that the tensioning jack applies 50% of the design stress. After holding the load for 2 minutes, increase the force applied by the tensioning jack to 110% of the design stress. After holding the load for 2 minutes, unload the load to zero.

[0049] By adopting the above technical solution, during the second tensioning, the load of the prestressed steel strand is gradually increased to 110% of the design stress for over-tensioning, thereby avoiding stress relaxation in the first-tensioned long side formwork section wall when tensioning the post-tensioned long side formwork section wall, thereby improving the tensioning quality and overall stability of the zigzag wall.

[0050] In a specific embodiment, the S8 comprises the following steps:

[0051] S81, pulling out the plastic plug mold in the cavity mold on one side of the tensioning end anchor assembly of the rear tensioning long side template segment, so that the inner cavity of the cavity mold is exposed;

[0052] S82. Clean the concrete and debris from the cavity of the mold, insert the tension anchor into the cavity of the mold, and position the prestressed steel strand in the anchor hole of the tension anchor. Then, place the clip over the prestressed steel strand and move the clip so that the clip engages in the anchor hole and the end face of the clip is flush with the end face of the tension anchor.

[0053] S83. Sleeve a tensioning jack over the prestressed steel strand, with the end of the tensioning jack contacting the side wall of the tensioning anchor. Connect a hydraulic drive device to the tensioning jack and adjust the hydraulic drive device so that the tensioning jack applies 50% of the design stress. The tensioning jack pulls the prestressed steel strand to extend. After holding the load for 2 minutes, increase the force applied by the tensioning jack to 80% of the design stress. Hold the load again for 2 minutes, then increase the force applied by the tensioning jack to 105% of the design stress. After holding the load for 2 minutes, unload the load to zero.

[0054] S83. Remove the tensioning jacks and cut off the excess prestressed steel strands;

[0055] S84, seal the anchor; inject concrete into the cavity mold to seal the prestressed steel strand.

[0056] By adopting the above technical solution, the post-tensioned elongated side formwork section wall is tensioned, which makes it easy to avoid cracks in the post-tensioned elongated side formwork section wall, thereby improving the overall strength and crack resistance of the serrated wall.

[0057] In summary, this application includes at least one of the following beneficial technical effects:

[0058] 1. The pre-tensioned long side formwork section wall is tensioned in stages, and the tension of the prestressed steel strand assembly is increased, slowly changing the local load of the prestressed steel strand and the serrated wall, so that the stress is released from the induced joint, which is convenient for reducing the cracks in the pre-tensioned long side formwork section, strengthening the crack control of the serrated wall, and also facilitating the avoidance of damage to the steel strand and the serrated wall.

[0059] 2. The pre-tensioned long side formwork section wall is tensioned multiple times to facilitate crack control at each stage of concrete solidification in the pre-tensioned long side formwork section wall.

[0060] 3. Over-tension the wall of the pre-tensioned long side formwork section to avoid stress relaxation in the pre-tensioned long side formwork section after the post-tensioned long side formwork section wall is tensioned, which affects the tensioning quality.

[0061] 4. After the induced joint is backfilled, the post-tensioned extended side formwork section wall is subjected to a single over-tensioning to reduce the occurrence of cracks in the post-tensioned extended side formwork section wall and further improve the overall crack resistance of the zigzag wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1This is a schematic diagram of the overall structure of a serrated wall of a storage ring tunnel in this embodiment.

[0063] Figure 2 This is a partial enlarged view of the serrated wall of a storage ring tunnel in this embodiment.

[0064] Figure 3 This is a schematic diagram of a crack control template structure for a serrated wall of a storage ring tunnel according to this embodiment.

[0065] Figure 4 This is a schematic diagram of the installation of prestressed anchors for a crack control template structure for a serrated wall of a storage ring tunnel according to this embodiment.

[0066] Figure 5 yes Figure 4 The enlarged view of part A is intended to illustrate the fixed end anchor assembly.

[0067] Figure 6 yes Figure 4 The enlarged view of part B is intended to illustrate the tension end anchor assembly.

[0068] Figure 7 This is a schematic diagram of the tensioning of the serrated wall of a storage ring tunnel in this embodiment.

[0069] Figure 8 yes Figure 7 The enlarged view of part C is intended to illustrate the installation structure of the tensioning jack and tensioning anchor.

[0070] Description of the accompanying drawings: 1. Support formwork; 11. Pre-tensioning formwork; 111. Pre-tensioning long side formwork section; 112. Pre-tensioning short side formwork section; 12. Post-tensioning formwork; 121. Post-tensioning long side formwork section; 1211. Partition; 122. Post-tensioning short side formwork section; 13. Steel cage; 14. Induced joint; 15. Diagonal brace; 16. Operating platform; 17. Support rod; 2. Prestressed anchor; 21. Prestressed steel strand; 22. Fixed end anchor assembly; 221. Extruded anchor head; 222. Fixed end pressure plate; 223. Fixed end spiral reinforcement; 23. Tensioning end anchor assembly; 231. Tensioning end spiral reinforcement; 232. Tensioning end pressure plate; 233. Hole mold; 234. Tensioning anchor; 235. Clip; 3. Tensioning jack. DETAILED DESCRIPTION

[0071] The embodiments of the present application disclose a storage ring tunnel sawtooth wall crack control template structure and construction method.

[0072] Reference Figure 1 and Figure 2 The zigzag wall of the storage ring tunnel is formed by connecting multiple independent zigzag walls end to end, and an induced joint 14 is set between two adjacent zigzag walls.

[0073] Reference Figure 3 and Figure 4 A storage ring tunnel zigzag wall crack control template structure, a single section zigzag wall is provided with a support template 1 and a prestressed anchor 2 before construction, the support template 1 includes a pre-tensioning template 11 and a post-tensioning template 12; the pre-tensioning template 11 and the post-tensioning template 12 are both provided with a steel cage 13; the pre-tensioning template 11 and the post-tensioning template 12 are both "L" shaped, a plurality of pre-tensioning templates 11 and the post-tensioning template 12 are arranged at intervals, and a plurality of pre-tensioning templates 11 and the post-tensioning template 12 are connected end to end to form a storage ring tunnel zigzag wall template; the pre-tensioning template 11 includes a pre-tensioning long side template segment 111 with a pre-tensioning long side template segment 111 and a pre-tensioning long side template segment 112. The post-tensioned formwork 12 includes a pre-tensioned short side formwork section 112, and a post-tensioned long side formwork section 121 and a post-tensioned short side formwork section 122. One end of the pre-tensioned long side formwork section 111 is connected to the pre-tensioned short side formwork section 112, and the other end is connected to the post-tensioned short side formwork section 122. A plurality of prestressed anchors 2 are respectively arranged in the pre-tensioned long side formwork section 111 and the post-tensioned long side formwork section 121, and the prestressed anchors 2 are fixedly connected to the steel cage 13. Two partitions 1211 are arranged in parallel in the post-tensioned formwork 12, and an induced joint 14 is formed between the two partitions 1211. A plurality of diagonal braces 15 are respectively arranged on both sides of the support formwork 1, and the plurality of diagonal braces 15 provide lateral support for the support formwork 1 to prevent the support formwork 1 from tilting and affecting the construction quality. An operating platform 16 is fixedly mounted on the top of the support formwork 1. Support rods 17 are installed between the support formwork 1 and the operating platform 16. One end of the support rod 17 is fixedly connected to the outer wall of the support formwork 1, and the other end is fixedly connected to the bottom wall of the operating platform 16. Multiple support rods 17 are evenly distributed along the length of the operating platform 16. During wall pouring construction, operators set up equipment and tools on the operating platform 16, which allows them to easily monitor the quality and progress of the construction.

[0074] Reference Figure 4 The prestressed anchor 2 includes a prestressed steel strand 21, a fixed-end anchor assembly 22 and a tensioning-end anchor assembly 23; the fixed-end anchor assembly 22 and the tensioning-end anchor assembly 23 are respectively arranged at both ends of the length direction of the prestressed steel strand 21; the prestressed steel strand 21 is fixedly set on the steel cage mesh 13, and the extension direction of the prestressed steel strand 21 is parallel to the length direction of the pre-tensioned elongated side formwork section 111 or the post-tensioned elongated side formwork section 121; the prestressed steel strand 21 on the post-tensioned elongated side formwork section 121 passes through the two partitions 1211 and the induced seam 14.

[0075] Reference Figure 5The fixed end anchor assembly 22 includes an extruded anchor head 221, a fixed end pressure plate 222 and a fixed end spiral rib 223; the extruded anchor head 221 is coaxially fixedly connected to one end of the prestressed steel strand 21, the fixed end pressure plate 222 and the fixed end spiral rib 223 are both sleeved on the prestressed steel strand 21, the fixed end pressure plate 222 is located between the extruded anchor head 221 and the fixed end spiral rib 223, and the two side walls of the fixed end pressure plate 222 are respectively connected to the extruded anchor head 221 and the fixed end spiral rib 223.

[0076] Reference Figure 6 The tensioning end anchor assembly 23 includes a tensioning end spiral rib 231, a tensioning end pressure plate 232, a cavity mold 233 and a tensioning anchor 234; the tensioning end spiral rib 231, the tensioning end pressure plate 232 and the cavity mold 233 are sleeved on the prestressed steel strand 21, the tensioning end pressure plate 232 is located between the tensioning end spiral rib 231 and the cavity mold 233, one end of the tensioning end pressure plate 232 is fixedly connected to the tensioning end spiral rib 231, and the other end is abutted against the cavity mold 233; the end of the cavity mold 233 away from the tensioning end pressure plate 232 is abutted against the end template of the first tensioning long side template segment 111 or the second tensioning long side template segment 121; the tensioning anchor 234 is arranged in the inner cavity of the cavity mold 233; the prestressed steel strand 21 passes through the first tensioning long side template segment 111 or the second tensioning long side template segment 121 close to the end template of the tensioning end anchor assembly 23.

[0077] Reference Figure 7 and Figure 8 The tensioning end anchor assembly 23 also includes a clip 235. An anchor hole is provided on the tensioning anchor 234. The clip 235 is engaged in the anchor hole. When prestressing is performed, the tensioning anchor 234 is embedded in the inner cavity of the hole mold 233, and one end of the prestressed steel strand 21 extends out of the hole mold 233 and passes through the clip 235; the end of the clip 235 is flush with the side wall of the tensioning anchor 234, and the end of the prestressed steel strand 21 away from the fixed end anchor assembly 22 is provided with a tensioning jack 3, and the end face of the tensioning jack 3 is in contact with the end face of the tensioning anchor 234 away from the tensioning end pressure plate 232.

[0078] The implementation principle of the crack control template structure of the serrated wall of a storage ring tunnel in this embodiment is as follows: when constructing the serrated wall of the storage ring tunnel, multiple single-section serrated walls are enclosed to form an annular area, and the storage ring tunnel is arranged on the inner side of the serrated wall. The span of the serrated wall is large, and there is a risk of cracking after the construction is completed, causing damage to the wall structure and affecting the quality of the building. When constructing the serrated wall, measurements and markings are first carried out to determine the position of casting the serrated wall, and a steel cage mesh 13 is tied and welded in the marked area of ​​the serrated wall. Then, prestressed anchors 2 are installed on the steel cage mesh 13 to provide preliminary preparation for prestressing. Then, a pre-tensioning template 11 and a post-tensioning template 12 are installed on the peripheral side of the steel cage mesh 13. The pre-tensioning template 11 and the post-tensioning template 12 together constitute a support template 1, and an induced joint 14 is provided on the post-tensioning long side template segment 121. An operating platform 16 is set on the top of the supporting formwork 1, and then the position of the induced joint 14 is reserved through the operating platform 16, and concrete is poured into the cavity of the supporting formwork 1 to form a zigzag wall. After the pouring is completed, the wall of the first-tensioned long side formwork section 111 is prestressed, so that the wall of the first-tensioned long side formwork section 111 shrinks. At the same time, during the tensioning, the induced joint 14 in the post-tensioned long side formwork section 121 tends to expand, and the stress inside the wall of the first-tensioned long side formwork section 111 is released from the position of the induced joint 14; after the wall of the first-tensioned long side formwork section 111 is tensioned, the induced joint 14 is poured, and then the wall of the post-tensioned long side formwork section 121 is tensioned, so that the wall of the post-tensioned long side formwork section 121 shrinks, so as to avoid cracks in the zigzag wall and improve the rigidity of the zigzag wall and the overall crack resistance.

[0079] In a second aspect, a method for constructing a zigzag wall crack control template structure for a storage ring tunnel comprises the following steps:

[0080] S1. Measure and mark, determine the construction position of the storage ring serrated wall according to the requirements of the design drawings, reserve the induction joint 14, and determine the construction position of the serrated wall on both sides of the induction joint 14.

[0081] S2. Binding and welding the steel cage mesh 13 within the construction position of the zigzag wall;

[0082] S3. Install the prestressed anchor 2 on the steel cage mesh 13; first, sleeve the prestressed steel strand 21 with an outer covering layer, which can be set as a high-density polyethylene extruded plastic tube, and use a rust-proof and anti-corrosion lubricating grease coating between the plastic tube and the prestressed steel strand 21. Then use an extruder to install the extruded anchor head 221 at one end of the prestressed steel strand 21. Place the prestressed steel strand 21 with the extruded anchor head 221 on the steel cage mesh 13 of the pre-tensioned long side formwork section 111 or the post-tensioned long side formwork section 121 to ensure that the prestressed steel strand 21 is placed horizontally; then sleeve the fixed end pressure plate 222 and the fixed end spiral rib 223 on the end of the prestressed steel strand 21 close to the extruded anchor head 221, the fixed end pressure plate 222 is fixedly connected to the extruded anchor head 221, and the fixed end spiral rib 223 is fixedly connected to the fixed end pressure plate 222; the tensioning end spiral rib 231 , the tensioning end pressure plate 232 and the hole mold 233 are sleeved on the other end of the prestressed steel strand 21, the tensioning end pressure plate 232 is located between the tensioning end spiral rib 231 and the hole mold 233, one end of the tensioning end pressure plate 232 is fixedly connected to the tensioning end spiral rib 231, and the other end is in contact with the hole mold 233. The prestressed steel strand 21 extends out of the steel cage mesh 13, and the steel cage mesh 13 is tied to the plastic tube on the prestressed steel strand 21 to fix the position of the prestressed steel strand 21, and a plastic plug mold is inserted into the inner cavity of the hole mold 233.

[0083] S4. Set up the supporting formwork 1 and the operating platform 16 around the steel cage mesh 13; bolt the formwork at both ends of the pre-tensioned long side formwork section 111 or the post-tensioned long side formwork section 121 to the fixed end pressure plate 222 and the tensioning end pressure plate 232 respectively to ensure that the fixed end pressure plate 222 and the tensioning end pressure plate 232 are firmly installed. At the same time, the end of the prestressed steel strand 21 close to the tensioning end anchor assembly 23 should pass through the end formwork of the pre-tensioned long side formwork section 111 or the post-tensioned long side formwork section 121, and the hole form 233 should be tightly pressed against the end formwork.

[0084] S5. Concrete pouring; Before pouring prestressed concrete, the support formwork 1, steel cage 13 and prestressed anchor 2 should be inspected. The gap between the cavity form 233 and the formwork should be filled; the operator should control the pouring progress and quality on the operating platform 16; at the same time, when pouring concrete in the support formwork 1, vibration should be carried out simultaneously, and the vibrating rod should not directly hit the prestressed anchor 2 to prevent damage to the connection part of the prestressed anchor 2. In key areas with dense steel bars such as prestressed tensioning ends and hidden column nodes, it is advisable to use a small-diameter vibrating rod or vibrating piece to carefully vibrate and compact them. When pouring, pay attention to check the position and size of the support formwork 1 and prestressed anchor 2. If loose, repair them in time.

[0085] S6. Prestress the wall of multiple sections of pre-tensioned long side formwork sections 111 multiple times; before tensioning, a tensioning scaffolding needs to be set up on one side of the tensioning end of the zigzag wall, and a tensioning jack 35 and a hydraulic drive device need to be arranged on the tensioning scaffolding so that the tensioning jack 3 is aligned with the tensioning anchor 234.

[0086] S6 includes the following steps:

[0087] S61. After the concrete strength reaches 40%, the end formwork of the pre-tensioned long side formwork section 111 close to the tensioning end is removed, and the wall of the pre-tensioned long side formwork section 111 is tensioned for the first time, and the tensioning control stress is maintained at 50% of the design stress.

[0088] S61 includes the following steps:

[0089] S611. Use testing equipment to test the concrete wall. After the concrete strength is measured to be 40%, remove the end formwork of the pre-tensioned long side formwork segment 111 close to the tensioning end anchor assembly 23, pull out the plastic plug mold of the cavity mold 233, and expose the inner cavity of the cavity mold 233.

[0090] S612. Clean the concrete and debris in the inner cavity of the hole mold 233, embed the tensioning anchor 234 into the inner cavity of the hole mold 233, and the prestressed steel strand 21 is located in the anchor hole of the tensioning anchor 234; then put the clip 235 on the prestressed steel strand 21, move the clip 235 so that the clip 235 is engaged in the anchor hole, and the end face of the clip 235 is flush with the end face of the tensioning anchor 234.

[0091] S613. Put the tensioning jack 3 on the prestressed steel strand 21, and the end of the tensioning jack 3 abuts against the side wall of the tensioning anchor 234. Connect the hydraulic drive device to the tensioning jack 3, and adjust the hydraulic drive device so that the tensioning jack 3 applies 10% of the design stress. The tensioning jack 3 pulls the prestressed steel strand 21 to stretch. After holding the load for 2 minutes, record the elongation value L1, and then increase the force of the tensioning jack 3 to 20% of the design stress. Hold the load for another 2 minutes and record the elongation value L2. Continue to increase the force of the tensioning jack 3 to 50% of the design stress. After holding the load for 2 minutes, record the elongation value L3, and finally unload to zero.

[0092] S614. Remove the tensioning jack 3 and temporarily cover the cavity mold 233 and the working surface of the prestressed tensioning end to ensure that the prestressed steel strand 21 at the tensioning end is not exposed to the outside and to prevent the prestressed steel strand 21 from rusting.

[0093] S62. After the concrete strength reaches 80%, the pre-tensioned long side formwork section 111 wall is tensioned for the second time, and the tensioning control stress is maintained at 110% of the design stress.

[0094] S62 includes the following steps:

[0095] S621. Use testing equipment to test the concrete wall. After the concrete strength is measured to be 80%, remove the temporary cover of the prestressed tensile end working surface.

[0096] S622. Reinstall the tensioning jack 3 and the hydraulic drive device; adjust the hydraulic drive device so that the tensioning jack 3 applies 50% of the design stress, holds the load for 2 minutes, and records the elongation value L4; then increase the force applied by the tensioning jack 3 to 110% of the design stress, holds the load for 2 minutes, and records the elongation value L5; finally, unload the load to zero; compare the elongation values ​​obtained by multiple stretching with the theoretically calculated elongation values, and control the error within 6%. When the elongation error exceeds 6%, the machine should be stopped to check the cause, and adjustments should be made before continuing tensioning.

[0097] S63. Remove the tensioning jack 3 and cut off the excess prestressed steel strand 21. After tensioning is completed, remove the tensioning jack 3 from the prestressed steel strand 21 and cut off the prestressed steel strand 21 extending beyond the cavity mold 233. Use an abrasive cutter to cut the material. Do not use gas cutting or electric welding to prevent annealing of the prestressed steel strand 21, which could affect its mechanical properties.

[0098] S64, sealing the anchor; injecting concrete into the cavity mold 233, sealing the prestressed steel strand 21 to ensure that the prestressed steel strand 21 does not expose the concrete wall.

[0099] S65. Repeat steps S61-S64 to perform prestressing on the wall of the multiple sections of pre-tensioned long side formwork sections 111.

[0100] S7. Remove the support formwork 1 and the operating platform 16, and perform grouting backfill on the induced joints 14; first remove the diagonal braces 15 and the support rods 17, remove the operating platform 16 from the top of the support formwork 1, and finally remove the support formwork 1 around the serrated wall, and then perform grouting backfill on the induced joints 14 between the multiple wall sections.

[0101] S8. Prestress the walls of the multiple post-tensioned long side formwork segments 121 respectively.

[0102] S62 includes the following steps:

[0103] S81. Pull out the plastic plug mold in the cavity mold 233 on one side of the tensioning end anchor assembly 23 of the rear tensioning long side template segment 121, so that the inner cavity of the cavity mold 233 is exposed.

[0104] S82. Clean the concrete and debris in the inner cavity of the hole mold 233, embed the tensioning anchor 234 into the inner cavity of the hole mold 233, and the prestressed steel strand 21 is located in the anchor hole of the tensioning anchor 234; then put the clip 235 on the prestressed steel strand 21, move the clip 235 so that the clip 235 is engaged in the anchor hole, and the end face of the clip 235 is flush with the end face of the tensioning anchor 234.

[0105] S83. Sleeve the tensioning jack 3 on the prestressed steel strand 21, with the end of the tensioning jack 3 abutting against the side wall of the tensioning anchor 234. Connect the hydraulic drive device to the tensioning jack 3, and adjust the hydraulic drive device so that the tensioning jack 3 applies 50% of the design stress. The tensioning jack 3 pulls the prestressed steel strand 21 to stretch. After holding the load for 2 minutes, increase the force of the tensioning jack 3 to 80% of the design stress. Hold the load for another 2 minutes, continue to increase the force of the tensioning jack 3 to 105% of the design stress, and unload to zero after holding the load for 2 minutes.

[0106] S83. Remove the tensioning jack 3 and cut off the redundant prestressed steel strands 21.

[0107] S84, sealing the anchor; injecting concrete into the cavity mold 233, sealing the prestressed steel strand 21, and completing the overall construction of the sawtooth wall.

[0108] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A storage ring tunnel sawtooth wall crack control template structure, characterized by: The invention comprises a support formwork (1) and a prestressed anchor (2), wherein the support formwork (1) comprises a pre-tensioning formwork (11) and a post-tensioning formwork (12); a steel cage (13) is provided in each of the pre-tensioning formwork (11) and the post-tensioning formwork (12); the pre-tensioning formwork (11) and the post-tensioning formwork (12) are both in an "L" shape, a plurality of the pre-tensioning formwork (11) and the post-tensioning formwork (12) are arranged at intervals, and a plurality of the pre-tensioning formwork (11) and the post-tensioning formwork (12) are connected end to end to form a sawtooth wall formwork of a storage ring tunnel; The pre-tensioning formwork (11) includes a pre-tensioning long side formwork section (111) and a pre-tensioning short side formwork section (112), and the post-tensioning formwork (12) includes a post-tensioning long side formwork section (121) and a post-tensioning short side formwork section (122); one end of the pre-tensioning long side formwork section (111) is connected to the pre-tensioning short side formwork section (112), and the other end is connected to the post-tensioning short side formwork section (122); a plurality of prestressed anchors (2) are respectively arranged in the pre-tensioning long side formwork section (111) and the post-tensioning long side formwork section (121), and the prestressed anchors (2) are fixedly connected to the steel cage mesh (13); Two partitions (1211) are arranged in the post-tensioning template (12), the two partitions (1211) are arranged in parallel, and an induced seam (14) is formed between the two partitions (1211).

2. The storage ring tunnel serrated wall crack control template structure according to claim 1, characterized in that: The prestressed anchor (2) comprises a prestressed steel strand (21), a fixed-end anchor assembly (22) and a tensioned-end anchor assembly (23); The fixed end anchor assembly (22) and the tensioning end anchor assembly (23) are respectively arranged at both ends of the length direction of the prestressed steel strand (21); the prestressed steel strand (21) is fixedly arranged on the steel cage (13), and the extension direction of the prestressed steel strand (21) is parallel to the length direction of the pre-tensioned elongated edge template section (111) or the post-tensioned elongated edge template section (121); The fixed-end anchor assembly (22) includes an extruded anchor head (221), a fixed-end pressure plate (222), and a fixed-end spiral rib (223); the extruded anchor head (221) is coaxially fixedly connected to one end of the prestressed steel strand (21); the fixed-end pressure plate (222) and the fixed-end spiral rib (223) are both sleeved on the prestressed steel strand (21); the fixed-end pressure plate (222) is located between the extruded anchor head (221) and the fixed-end spiral rib (223); and the two side walls of the fixed-end pressure plate (222) are respectively connected to the extruded anchor head (221) and the fixed-end spiral rib (223); The tensioning end anchor assembly (23) comprises a tensioning end spiral rib (231), a tensioning end pressure plate (232), a cavity mold (233) and a tensioning anchor (234); the tensioning end spiral rib (231), the tensioning end pressure plate (232) and the cavity mold (233) are all sleeved on the prestressed steel strand (21), and the tensioning end pressure plate (232) is located between the tensioning end spiral rib (231) and the cavity mold (233). ), one end of the tensioning end pressure plate (232) is fixedly connected to the tensioning end spiral rib (231), and the other end abuts against the cavity mold (233); one end of the cavity mold (233) away from the tensioning end pressure plate (232) abuts against the end template of the first tensioning long side template segment (111) or the second tensioning long side template segment (121); the tensioning anchor (234) is arranged in the inner cavity of the cavity mold (233); The prestressed steel strand (21) passes through the end formwork of the pre-tensioned elongated side formwork section (111) or the post-tensioned elongated side formwork section (121) close to the tensioned end anchor assembly (23).

3. The storage ring tunnel serrated wall crack control template structure according to claim 2, characterized in that: The tensioning end anchor assembly (23) further includes a clip (235), an anchor hole is provided on the tensioning anchor (234), the clip (235) is engaged in the anchor hole, the tensioning anchor (234) is embedded in the inner cavity of the cavity mold (233), and one end of the prestressed steel strand (21) extends out of the cavity mold (233) and passes through the clip (235); the end of the clip (235) is flush with the side wall of the tensioning anchor (234), and the end of the prestressed steel strand (21) away from the fixed end anchor assembly (22) is provided with a tensioning jack (3), and the end face of the tensioning jack (3) is in contact with the end face of the tensioning anchor (234) away from the tensioning end pressure plate (232).

4. The storage ring tunnel serrated wall crack control template structure according to claim 1, characterized in that: The support formwork (1) further comprises diagonal braces (15), and a plurality of the diagonal braces (15) are respectively arranged on both sides of the support formwork (1).

5. The storage ring tunnel serrated wall crack control template structure according to claim 1, characterized in that: The support formwork (1) further comprises an operating platform (16) and a plurality of support rods (17), wherein the operating platform (16) is fixedly arranged on the top wall of the support formwork (1), and one end of the support rod (17) is fixedly connected to the outer wall of the support formwork (1), and the other end is fixedly connected to the bottom wall of the operating platform (16), and the plurality of support rods (17) are evenly distributed along the length direction of the operating platform (16).

6. A method for constructing a zigzag wall crack control template structure for a storage ring tunnel, comprising the zigzag wall crack control template structure for a storage ring tunnel according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Measure and mark, determine the construction position of the storage ring serrated wall according to the requirements of the design drawings, reserve an induction seam (14), and determine the construction position of the serrated wall on both sides of the induction seam (14); S2, tying and welding the steel cage (13) within the construction position of the sawtooth wall; S3, installing prestressed anchors (2) on the steel cage (13); S4, setting up a supporting template (1) and an operating platform (16) around the steel cage (13); S5, concrete pouring; S6, prestressing the wall of the multiple pre-tensioned long side formwork sections (111) for multiple times; S7, dismantling the support formwork (1) and the operating platform (16), and backfilling the induced joint (14) with grouting; S8. Prestressing is performed on the walls of the multiple sections of post-tensioned long side formwork sections (121).

7. The construction method of a storage ring tunnel serrated wall crack control template structure according to claim 6, characterized in that: The S6 comprises the following steps: S61. After the concrete strength reaches 40%, the end formwork of the pre-tensioned long side formwork section (111) close to the tensioning end is removed, and the wall of the pre-tensioned long side formwork section (111) is tensioned for the first time, and the tensioning control stress is maintained at 50% of the design stress; S62, after the concrete strength reaches 80%, the wall of the pre-tensioned long side formwork section (111) is tensioned for the second time, and the tensioning control stress is maintained at 110% of the design stress; S63, remove the tensioning jack (3), and cut off the excess prestressed steel strands (21); S64, sealing the anchor; injecting concrete into the cavity mold (233) to seal the prestressed steel strand (21); S65, prestressing the wall of the multiple sections of post-tensioned long side formwork sections (121).

8. The construction method of the serrated wall crack control template structure for a storage ring tunnel according to claim 7 is characterized in that: The S61 includes the following steps: S611, using a testing device to test the concrete wall, after measuring that the concrete strength reaches 40%, remove the end formwork of the pre-tensioned long side formwork section (111) close to the tensioning end anchor assembly (23), and pull out the plastic plug mold of the cavity mold (233) to expose the inner cavity of the cavity mold (233); S612, clean the concrete and debris in the inner cavity of the cavity mold (233), embed the tension anchor (234) into the inner cavity of the cavity mold (233), and position the prestressed steel strand (21) in the anchor hole of the tension anchor (234); then sleeve the clip (235) on the prestressed steel strand (21), and move the clip (235) so that the clip (235) is engaged in the anchor hole, and the end face of the clip (235) is flush with the end face of the tension anchor (234); S613, sleeve the tensioning jack (3) on the prestressed steel strand (21), the end of the tensioning jack (3) abuts against the side wall of the tensioning anchor (234), connect the hydraulic drive device to the tensioning jack (3), adjust the hydraulic drive device so that the tensioning jack (3) applies 10% of the design stress, the tensioning jack (3) pulls the prestressed steel strand (21) to stretch, after holding the load for 2 minutes, increase the force of the tensioning jack (3) to 20% of the design stress, hold the load again for 2 minutes, continue to increase the force of the tensioning jack (3) to 50% of the design stress, and unload to zero after holding the load for 2 minutes; S614, remove the tensioning jack (3), and temporarily cover the cavity mold (233) and the prestressed tensioning end working surface.

9. The construction method of a storage ring tunnel serrated wall crack control template structure according to claim 7, characterized in that: The S62 includes the following steps: S621. Use testing equipment to test the concrete wall. Once the concrete strength reaches 80%, remove the temporary cover on the prestressed tension end working surface. S622. Install the tensioning jack (3) and the hydraulic drive device again; adjust the hydraulic drive device so that the tensioning jack (3) applies 50% of the design stress. After holding the load for 2 minutes, increase the force applied by the tensioning jack (3) to 110% of the design stress. After holding the load for 2 minutes, unload the load to zero.

10. The construction method of a storage ring tunnel serrated wall crack control template structure according to claim 7, characterized in that: The S8 comprises the following steps: S81, pulling out the plastic plug mold in the cavity mold (233) on one side of the tensioned long side template section (121) close to the tensioned end anchor assembly (23), so that the inner cavity of the cavity mold (233) is exposed; S82, clean the concrete and debris in the inner cavity of the cavity mold (233), embed the tension anchor (234) into the inner cavity of the cavity mold (233), and position the prestressed steel strand (21) in the anchor hole of the tension anchor (234); then sleeve the clip (235) on the prestressed steel strand (21), and move the clip (235) so that the clip (235) is engaged in the anchor hole, and the end face of the clip (235) is flush with the end face of the tension anchor (234); S83, sleeve the tensioning jack (3) on the prestressed steel strand (21), the end of the tensioning jack (3) abuts against the side wall of the tensioning anchor (234), connect the hydraulic drive device to the tensioning jack (3), adjust the hydraulic drive device so that the tensioning jack (3) applies 50% of the design stress, the tensioning jack (3) pulls the prestressed steel strand (21) to stretch, after holding the load for 2 minutes, increase the force of the tensioning jack (3) to 80% of the design stress, hold the load again for 2 minutes, continue to increase the force of the tensioning jack (3) to 105% of the design stress, and unload to zero after holding the load for 2 minutes; S83, remove the tensioning jack (3), and cut off the excess prestressed steel strands (21); S84, sealing the anchor; injecting concrete into the cavity mold (233), sealing the prestressed steel strand (21), and completing the overall construction of the sawtooth wall.

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