Integrated casting system for inner wall panels and top brackets of super-large diameter tunnels

Abstract

The present invention discloses an integrated casting system for inner wall panels and top brackets of super-large diameter tunnels, which includes a trolley, a top bracket casting module, and a wall panel casting module. On the one hand, the present invention can simultaneously cast the top bracket and the inner side wall after positioning the frame once, which not only makes the process of mold closing and demoulding simple and safe, but also effectively shortens the construction period and greatly increases the efficiency of casting construction. In addition, it is very suitable for construction in relatively narrow tunnels.

Description

Technical Field

[0001] The invention belongs to the technical field of shield tunnel construction, and in particular relates to an integrated casting system for inner wall panels and top corbels of an ultra-large diameter tunnel. Background Art

[0002] At present, except for the middle box culvert which is constructed by prefabrication, the rest of the internal structure of the shield section of the tunnel project is constructed by cast-in-place method, mainly including the lining and the lane slabs on both sides of the box culvert, cast-in-place flue slabs of the fan section, cast-in-place corbels, curved slabs on both sides of the tunnel, straight slab walls and evacuation stairs, etc. For example, the roughening between the contact surface between the cast-in-place corbels and the pipe segments is done by blowing away the concrete residue with an air gun, and then washing it with high-pressure water to ensure that the roughened concrete surface is clean; then the reinforcement is planted at the connection between the corbels and the pipe segments; then the formwork is lifted by a disc-type scaffolding to form a casting cavity, and finally the concrete is poured and the formwork is removed.

[0003] However, in the pouring construction, the steps formed by each pouring section are similar, and there are the following technical defects:

[0004] 1. The process of forming a casting cavity or removing the mold is very complicated when the on-site casting is completed in the limited space of the shield. In addition, under the restrictions of some angles and heights, it is not only inconvenient to implement, but also has low construction efficiency. At the same time, there are great deficiencies in the strength of the casting cavity and construction safety.

[0005] 2. Since the on-site pouring is carried out sequentially, the corbels and inner wall panels or flue panels are formed separately, which greatly increases the construction period. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a new integrated casting system for the inner wall panels and top corbels of a super-large diameter tunnel.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: an integrated casting system for inner wall panels and top corbels of a super-large diameter tunnel, comprising: a trolley, which comprises a base, a frame located on the base, and a walking component arranged at the bottom of the base and capable of switching between walking and positioning in the tunnel;

[0008] The top corbel casting module is located at the top of the frame and at one side of the frame in the length direction, and the corbel casting module includes a corbel bracket arranged on the frame in a relatively movable manner, and a corbel template arranged on the corbel bracket, wherein the corbel bracket moves up and down and in a direction of approaching and moving away from the tunnel segment, and is moved in a direction of approaching and moving away from the tunnel segment to form a casting mold cavity, and is moved away from the relative demoulding;

[0009] A wall panel casting module; it is located below the same side of the corbel casting module, and the wall panel casting module includes a bottom support frame extending outward from the bottom of a frame, an arm frame whose lower end is rotated and slidably arranged on the outer end of the bottom support frame, a wall formwork arranged on the outer side of the arm frame, an external connecting part detachably connected to the embedded part through a connector, and a telescopic support rod arranged between the arm frame and the frame, wherein during the telescopic movement of the telescopic support rod, the lower end of the arm frame is used as the movement center to move close to the tunnel segment to form a casting cavity or away from the demoulding.

[0010] Preferably, the corbel support comprises a plurality of struts arranged in a stacked and intersecting manner, wherein the top surfaces of the plurality of struts constitute a supporting surface, and the corbel template comprises a plurality of assembled templates assembled side by side and erected on the supporting surface.

[0011] Furthermore, the assembled template includes a first template located at the bottom and extending horizontally from the inside to the outside, a second template extending obliquely upward from the inner end of the first template, and a third template assembled on the upper end of the second template by rotating around the horizontal direction, and a plurality of support rods are respectively supported at the bottom of the first template and the second template. In this way, a mold cavity is formed to meet the casting needs, and it is also convenient for the rapid disassembly and assembly of the template.

[0012] According to a specific implementation and preferred aspect of the present invention, the plurality of support rods include a first rod and a second rod extending along the length and width direction of the frame respectively, and a third rod inclined from bottom to top, wherein the plurality of first rods and the plurality of second rods are laid flat at intervals, and the plurality of first rods are erected on the plurality of second rods, the first template intersects with the first rods and is erected on a support surface formed by the tops of the plurality of first rods, and the upper end of the third rod is supported on the bottom of the second template. With the combination of the plurality of rods, a stable support can be formed to facilitate the implementation of pouring and increase the safety of construction.

[0013] According to another specific implementation and preferred aspect of the present invention, the top corbel casting module also includes a lifting component, a lateral moving component, and a flipping component, wherein the lifting component includes a plurality of lifting rods extending in the up-down direction and synchronously telescopically moving, the lateral moving component includes a plurality of lateral moving rods extending in the width direction of the frame and synchronously telescopically moving, and the flipping component includes a single flipping shaft that crosses the connection between the third template and the second template, wherein the third template rotates relative to the second template during the forward and reverse rotation of the flipping shaft. Under the fine adjustment of the three movements, the corbel template can be moved to the specified position to ensure the rapid formation of the mold cavity.

[0014] According to another specific implementation and preferred aspect of the present invention, there are multiple bottom support frames arranged side by side along the length direction of the vehicle frame, the arm frames are arranged one by one with the bottom support frames, and the wall formwork is composed of multiple pieces spliced ​​together, wherein the multiple wall formworks and the arm frames are fixedly connected by multiple connecting rods. This arrangement can enhance the strength of the wall formwork and avoid displacement or deformation of the wall formwork caused by pouring.

[0015] Preferably, the bottom support frame includes a first support rod extending from top to bottom and from inside to outside, a second support rod extending horizontally from the outer end of the first support rod, and the arm frame includes a first arm rod arranged parallel to the wall formwork, a second arm rod bent inward from the lower end of the first arm rod, and the lower end of the second arm rod is slidably and rotatably connected with the outer end of the second support rod along the horizontal direction. The use of the bent arm rod for assembly not only avoids excessive instantaneous force at the center of rotation, but also decomposes the force into horizontal and vertical directions, thereby obtaining a stable mold cavity structure; it also shortens the movement stroke of the telescopic support rod, making it more convenient and safe to implement mold opening or mold closing actions.

[0016] Furthermore, the connecting rod is vertically arranged with the first arm, and a reinforcing rod is also arranged on the first support rod, wherein the reinforcing rod comprises a first reinforcing rod fixed on the vehicle frame and the first arm, and a second reinforcing rod diagonally supported between the first reinforcing rod and the first arm, thereby avoiding damage to the bottom support frame due to transitional force, and further improving construction safety.

[0017] According to another specific implementation and preferred aspect of the present invention, a platform bracket is further provided on the upper part of each first arm, the platform bracket and the first arm form a tripod rod of a right triangle, and an extension rod extends upward from the end of the tripod away from the first arm. In this way, after laying the board on the tripod rod, it is convenient for the workers to walk into the opening of the side wall mold cavity, thereby facilitating casting and construction.

[0018] Preferably, the telescopic struts are arranged in one-to-one correspondence with the first arm, and at least two telescopic struts are arranged between each first arm and the second reinforcing rod, wherein the movement of the two telescopic struts drives the first arm to relatively flip and move horizontally around the lower end. The advantage of such an arrangement is that under the relative interlocking of multiple rods, the supporting force required to form the casting mold cavity is greatly increased, and deformation of the wall formwork caused by concrete pouring is avoided; at the same time, it is also convenient for mold closing and demoulding operations.

[0019] In addition, the frame is stacked up and down and has at least two layers. It only needs to meet the height that can be used to install the corbel, and stairs and handrails can be added between the upper and lower layers to facilitate the staff to simultaneously implement the construction of the side wall and the corbel.

[0020] Preferably, the walking component comprises a plurality of walking wheels located at the bottom of the base, and support legs arranged on the base and capable of being extended up and down, wherein the support legs are supported on the tunnel walking surface and enable the walking wheels to be separated from the tunnel walking surface to position the vehicle frame;

[0021] Preferably, a guardrail is provided on the top layer of the frame to improve the safety of the construction.

[0022] Due to the implementation of the above technical solution, the present invention has the following advantages compared with the prior art:

[0023] On the one hand, after the frame is positioned once, the present invention can simultaneously cast the top corbel and the internal side wall, which not only makes the mold closing and demoulding processes simple and the construction safe, but also effectively shortens the construction period and greatly increases the efficiency of the casting construction. In addition, it is very suitable for construction in tunnels with relatively narrow spaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the integrated casting system of the inner wall panel and top corbel of a super-large diameter tunnel of the present invention;

[0025] Figure 2 for Figure 1 Schematic diagram of structural decomposition;

[0026] Figure 3 for Figure 1 A schematic diagram of the main view;

[0027] Figure 4 for Figure 3 A rear view schematic diagram of

[0028] Figure 5 for Figure 3 Schematic diagram of the left side;

[0029] Figure 6 for Figure 1 Schematic diagram of the structure of the middle inner wall panel in the mold closing state (omitting the top corbel casting module);

[0030] Figure 7 for Figure 6 Schematic diagram of the structure of the middle inner wall panel in the demoulding state (omitting the top corbel casting module);

[0031] Figure 8 for Figure 1 Structural schematic diagram of the middle top corbel casting module in the mold closing state (omitting the wall panel casting module);

[0032] Fig. 9 for Figure 8 Structural schematic diagram of the middle top corbel casting module in the demoulding state (omitting the wall panel casting module);

[0033] Among them: 1. trolley; 10. base; 11. frame; 12. walking parts; 120. walking wheels; 121. support legs; 122. auxiliary support legs; 13. guardrail; 2. top corbel casting module; 20. corbel bracket; 200. support rod; g1. first rod; g2. second rod; g3. third rod; 21. corbel template; 210. assembly template; a1. first template; a2. second template; a3. third template; 22. lifting parts; 220. lifting rod; 23. transverse moving parts; 23 0. Transverse rod; 24. Flipping component; 240. Flipping axis; 3. Wall panel casting module; 30. Bottom support frame; 301. First support rod; 302. Second support rod; 31. Arm; 311. First arm; 312. Second arm; 32. Wall formwork; 33. Embedded parts; 34. Connector; 35. External parts; 36. Telescopic support rod; 37. Reinforcement rod; 371. First reinforcement rod; 372. Second reinforcement rod; 38. Platform bracket; 380. Tripod; 381. Extension frame rod; 39. Connecting rod. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0035] like Figure 1 and Figure 2 As shown, the present embodiment involves an integrated casting system for inner wall panels and top corbels of super-large diameter tunnels, which includes a trolley 1, a top corbel casting module 2, and a wall panel casting module 3.

[0036] Specifically, the trolley 1 includes a base 10, a frame 11 located on the base 10, and a traveling component 12 disposed at the bottom of the base 10 and capable of switching between traveling and positioning in a tunnel.

[0037] The base 10 is rectangular, and the frame 11 is divided into three layers from bottom to top, wherein stairs and handrails are provided between two adjacent layers.

[0038] The walking component 12 includes two sets of walking wheels 120 located at the bottom of the base 10, support legs 121 arranged at the four corners of the base 10 and capable of being extended and retracted up and down, and auxiliary support legs 122, wherein the support legs 121 and the auxiliary support legs 122 are supported on the tunnel walking surface and allow the walking wheels to detach from the tunnel walking surface to position the frame 11.

[0039] In this example, in order to improve the stability of the positioning support, a plurality of telescopic legs are further provided at the bottom of the base 10, wherein the entire trolley and the tunnel walking surface are supported together by the plurality of telescopic legs and four support legs 121. In this way, the positioning is stable; at the same time, the switching support of the two sets of running wheels 120 is used to implement the trolley to walk freely on the tunnel walking surface.

[0040] At the same time, a guardrail 13 is also provided on the top layer of the vehicle frame 11. To improve the safety of construction, the specific guardrail 13 only needs to surround three sides, and the gap side formed faces the tunnel segment. At this time, under the premise of ensuring construction safety, it is not only more convenient to install the top bracket, but also forms a good avoidance space, which is more conducive to the pouring construction.

[0041] Combination Figures 3 to 5 As shown, the top corbel casting module 2 is located at the top of the frame 11 and at the side of the length direction of the frame 11, and the corbel casting module 2 includes a corbel bracket 20 arranged on the frame 11 for relative movement, a corbel template 21 arranged on the corbel bracket 20, a lifting component 22, a transverse moving component 23, and a flipping component 24.

[0042] The wall panel casting module 3 is located below the same side of the corbel casting module 2, and the wall panel casting module 3 includes a bottom support frame 30 extending outward from the bottom of the frame 11, an arm frame 31 whose lower end is rotated and slidably arranged on the outer end of the bottom support frame 30, a wall formwork 32 arranged on the outside of the arm frame 31, an external connection part 35 detachably connected to the embedded part 33 through a connector 34, and a telescopic support rod 36 arranged between the arm frame 31 and the frame 11.

[0043] Specifically, the corbel support 20 includes a plurality of struts 200 stacked and intersecting, wherein the top surfaces of the plurality of struts 200 constitute a supporting surface, and the corbel template 21 includes a plurality of assembly templates 210 assembled side by side and erected on the supporting surface.

[0044] The assembly template 210 includes a first template a1 located at the bottom and extending horizontally from the inside to the outside, a second template a2 extending obliquely upward from the inner end of the first template a1, and a third template a3 assembled on the upper end of the second template a2 by rotating around the horizontal direction. A plurality of support rods 200 are respectively supported at the bottom of the first template a1 and the second template a2. In this way, a mold cavity is formed to meet the casting needs and also facilitate the rapid disassembly and assembly of the template.

[0045] The plurality of support rods 200 include a first rod g1 and a second rod g2 extending along the length and width direction of the vehicle frame 11, respectively, and a third rod g3 inclined from bottom to top, wherein the plurality of first rods g1 and the plurality of second rods g2 are laid flat at intervals, and the plurality of first rods g1 are erected on the plurality of second rods g2, the first template a1 intersects with the first rods g1 and is erected on the support surface formed by the top of the plurality of first rods g1, and the upper end of the third rod g3 is supported on the bottom of the second template a2. With the combination of the plurality of rods, a stable support can be formed to facilitate the implementation of pouring and increase the safety of construction.

[0046] The lifting component 22 includes a plurality of lifting rods 220 extending in the up-down direction and synchronously telescopically moving, the transverse component 23 includes a plurality of transverse rods 230 extending in the width direction of the frame 11 and synchronously telescopically moving (conventional telescopic movement), and the flip component 24 includes a single flip shaft 240 crossing the connection between the third template a3 and the second template a2, wherein the third template a3 rotates relative to the second template a2 during the forward and reverse rotation of the flip shaft (conventional flip movement). Under the fine adjustment of the three movements, the corbel template can be moved to the specified position to ensure the rapid formation of the mold cavity.

[0047] There are multiple bottom support frames 30 and they are arranged side by side along the length direction of the vehicle frame 11. The arm frames 31 are arranged one by one with the bottom support frames 30. The wall formwork 32 is composed of multiple pieces, wherein the multiple wall formworks 32 and the arm frames 31 are fixedly connected by multiple connecting rods 39. This arrangement can enhance the strength of the wall formwork and avoid displacement or deformation of the wall formwork caused by pouring.

[0048] The bottom support frame 30 includes a first support rod 301 extending from top to bottom and from inside to outside, and a second support rod 302 extending horizontally from the outer end of the first support rod 301. The arm frame 31 includes a first arm rod 311 arranged parallel to the wall template, and a second arm rod 312 bent inward from the lower end of the first arm rod 311. The lower end of the second arm rod 312 is slidably and rotatably connected with the outer end of the second support rod 302 along the horizontal direction. The use of the bent arm rod for assembly not only avoids excessive instantaneous force at the center of rotation, but also decomposes the force into horizontal and vertical directions, thereby obtaining a stable mold cavity structure; it also shortens the movement stroke of the telescopic support rod, making it more convenient and safe to implement mold opening or mold closing actions.

[0049] The connecting rod 39 is vertically arranged with the first arm 311, and a reinforcing rod 37 is also arranged on the first support rod 301, wherein the reinforcing rod 37 comprises a first reinforcing rod 371 fixed on the vehicle frame 11 and the first arm 311, and a second reinforcing rod 372 diagonally supported between the first reinforcing rod 371 and the first arm 311. This avoids damage to the bottom support frame due to transitional force, and further improves construction safety.

[0050] The telescopic support rods 36 are arranged one by one with the bottom support frame 30 , and two telescopic support rods 36 are arranged between the bottom support frame 30 and the reinforcing rod 37 , wherein the two ends of each telescopic support rod 36 are respectively hinged to the second reinforcing rod 372 and the first arm rod 311 .

[0051] A platform support 38 is also provided on the upper part of each first arm 311, and the platform support 38 and the first arm 311 form a right-angled triangle tripod rod 380, and an extension rod 381 extending upward from the end of the tripod 380 away from the first arm 311. In this way, after the planks are laid on the tripod rod 380, it is convenient for the workers to walk into the opening of the side wall mold cavity, thereby facilitating pouring and construction.

[0052] Combine 6 and Figure 7 As shown in the figure, the pouring process of the top corbel is as follows:

[0053] Mold closing state: When the trolley 1 moves to the position to be poured on the tunnel walking surface, the walking part 2 first switches the top support of the supporting legs to position the trolley at the specified position. At this time, the mold is closed on the top and bottom, front and back (close to the direction of the pipe segment) of the corbel template 21, and the third template a3 is flipped to form a corbel pouring cavity between the corbel template 21 and the pipe segment, and then the steel cage is assembled and concrete is poured.

[0054] De-moulding state: the flipping component 24 drives the third formwork a3 to flip inward to disengage the top corbel, while the corbel bracket 20 falls and moves inward to disengage the pipe segment, and then, under the switching of the walking wheel 120 and the support, the walking wheel 120 is supported on the tunnel walking surface, and the bottom of the supporting leg is detached from the tunnel walking surface. At this time, under the power drive of the walking wheel 120, the entire casting system can be implemented to move on the tunnel walking surface.

[0055] Combination Figure 8 and Fig. 9 As shown, the pouring process of the side wall formwork is as follows:

[0056] Mold closing state: When the trolley moves to the position to be poured on the tunnel walking surface, the embedded screw 33 is first docked by the connector 34 and the external connector 35, and the arm 31 is flipped and attached to the pipe segment under the movement of the telescopic support rod 36 (the two telescopic support rods 36 maintain intersecting support), until it is flipped into place, and a pouring cavity is formed between the wall formwork 32 and the pipe segment, and then concrete pouring is implemented.

[0057] Demolding state: first remove the connector 34 and the external part 35, then remove the telescopic struts 36 that are close to the movement, and under the reset of another set of telescopic struts 36, the arm 31 is turned over and away from the pipe segment.

[0058] In addition, in this example, the above-mentioned top corbel structure is briefly introduced in combination with the embodiment as follows.

[0059] 1. Template trolley design

[0060] This design needs to solve the problem of tunnel internal arch corbel casting, change the traditional disk-type scaffolding supporting formwork casting method, enhance casting safety, and improve casting efficiency. The trolley designed for this project is 10.5m per section, and the connection is bolted.

[0061] The corbel trolley is mainly divided into three parts: the trolley base, the middle bracket and the corbel template.

[0062] 1. Trolley base

[0063] The trolley base consists of a main frame beam, a hydraulic lifting system, an electric control walking system, and an overall support system.

[0064] (1) Main frame beam

[0065] It is welded by 400*200*8*13mm H-shaped steel, and the webs and ribs are welded on both sides of the main beam to increase the strength of the main beam. Four hydraulic cylinder top supports are welded with 16mm steel plates at both ends of the base, and flanges are used to connect the cylinders. The welded base at the bottom of the main beam is connected to the support screw.

[0066] (2) Hydraulic lifting system

[0067] It consists of 4 hydraulic cylinders, a hydraulic pump station, hydraulic oil circuits, and a hydraulic control cabinet. The hydraulic lifting system is mainly used for the closing and demoulding of the top corbel template, as well as the steering support of the steering wheel during walking.

[0068] (3)Electronic control travel system

[0069] It consists of 4 electric steering wheels, a reduction motor, wires, and a control cabinet. The 4 electric steering wheels can rotate simultaneously or two of them can steer individually. It reduces the turning radius, increases flexibility, and facilitates driving in tunnels.

[0070] (4) Overall support system

[0071] It is composed of 12 adjustable screw rods. When the hydraulic cylinder is raised, the bottom screw rod is manually adjusted out to support the whole trolley and prevent the hydraulic cylinder from losing pressure.

[0072] 2. Middle layer support

[0073] (1) One layer of support

[0074] The bracket is welded with 120*120*5mm square tubes, and the bottom and top of the bracket are welded with patterned plates to serve as a construction platform. A pedestrian staircase is set up in the bracket to facilitate construction workers to go up and down. The lower end of the bracket is connected and fixed with the trolley base with fastening bolts.

[0075] (2) Second layer bracket

[0076] The material is the same as the first-layer bracket, and the second-layer bracket is also fastened with bolts. The top welding support plate and the adjusting screw are connected to the bracket template. The square pipe groove is welded on the upper end of the platform to facilitate the installation of the upper construction platform guardrail.

[0077] 3. Corbel template

[0078] The corbel template is 1.5 meters long, and a set of templates consists of 7 templates, totaling 10.5 meters. The single templates are connected by bolts. The bottom of the template is a template bracket, which is fixed to the second-layer bracket by welding. The template bracket can meet the template adjustment of 0-50mm up and down, and 0-100mm front and back.

[0079] 2. Formwork construction

[0080] ①. Template positioning and fixing

[0081] After the steel bar binding acceptance is completed, the template trolley is moved into place, and the corbel position template is positioned by adjusting the trolley. After completion, the template is re-measured and adjusted to the accurate position.

[0082] The template uses a standard steel template, which is tailor-made according to the shape of the cast-in-place corbel. The templates are fastened with bolts, and the steel template is fixed to the template bracket and the bracket at the bottom of the template by welding. The plugging mold uses a pre-processed standard template or wooden template. The plugging mold is fixed by a wire rod + steel pipe. The wire rod is welded to the main reinforcement to prevent the template from floating.

[0083] The template gap should not be larger than 2mm, and the template gap should be sealed with tape or PEVA to ensure that there is no leakage when pouring concrete. When constructing the template, the cross section must be correct, the surface must be flat, the joints must be tight, and the support must be firm. After the template is installed, the next process can be carried out only after the full-time quality inspector has passed the inspection.

[0084] ②、Buried pipes at the corbel

[0085] Drain pipes at the lowest point need to be arranged on both sides of the corbels. The drainage pipes of the fan heightening section should be arranged at the slope change points where water may accumulate. For each electric smoke exhaust outlet, a DN100 threading pipe should be pre-buried on the side of the cable corridor. The expansion joint between the top cast-in-place lining and the corbel should correspond to the bottom, and fire-resistant sealant should be used to caulk the three sides of the corbel expansion joint (except the segment side).

[0086] ③. Concrete construction

[0087] Cast-in-place corbels are constructed with bracket formwork, using C40 concrete and 1.5kg / m3 of polypropylene fiber. The main reinforcement protection layer is 40mm, the net distance deviation between the left and right corbels at the same mileage should not exceed 20mm, the height difference between the left and right corbels at the same mileage should not exceed 5mm, and the flatness of the top surface of the corbel should not exceed 0.5mm.

[0088] 1. Concrete into the mold

[0089] The cast-in-place corbel is constructed by ground pumping. The concrete ground pump is placed on the completed roadway slab and moves with the forward movement of the synchronous construction work surface. Before pumping concrete, the clean water in the storage hopper is pumped out from the pipeline to achieve the purpose of wetting and cleaning the pipeline. Then add cement mortar with the same proportion as the concrete into the hopper, and start pumping concrete after lubricating the pipeline; when starting to pump, the pumping speed should be slowed down, and the oil pressure change should be within the allowable value range. When the pumping is smooth, the normal speed is used for pumping. Concrete pumping should be continuous. When the concrete supply is not timely, the pumping speed needs to be reduced. When the pumping is temporarily interrupted, the mixing shall not be stopped.

[0090] 2. Concrete pouring

[0091] (1) Two Φ50 high-frequency insertion vibrators are equipped for compaction during pouring. The vibration points are arranged in a plum blossom shape, with the spacing between each point not exceeding 50 cm. The vibration points should follow the principle of "fast insertion and slow withdrawal". Vibration must be completed in time without missing any vibrations. The vibration time is based on when no more bubbles emerge and the concrete no longer sinks.

[0092] (2) Strengthen the vibration of concrete in areas with dense reinforcement to ensure compaction. When inserting the vibrator, it should not collide with reinforcement, embedded parts, or formwork.

[0093] (3) Before pouring concrete, mark the control elevation, and the spacing should not be greater than 6m. When the concrete surface is leveled, use the elevation control ruler to control the surface elevation according to the elevation control mark.

[0094] (4) After pouring, timely maintenance should be carried out to prevent concrete cracking and improve strength as soon as possible.

[0095] (5) The concrete surface is leveled with a scraper, rolled twice with an iron roller to remove the water seeping from the concrete surface, and then polished with a wooden shovel to make it smooth. After the water is absorbed, it is polished again with a wooden shovel to eliminate water absorption cracks.

[0096] 3. Concrete maintenance

[0097] (1) After the concrete is poured and formed, its upper surface is required to be smoothed and polished.

[0098] (2) The calendering time depends on the temperature and the solidification of the concrete. Generally, it is based on the slight flat indentation left by hand. The calendering process is adopted with two times of spreading and pressing.

[0099] A. Rough leveling: Use a steel trowel to scrape off excess concrete (or fill in depressions) and perform rough leveling. When the concrete absorbs water and begins to set, use a trowel to smooth the surface to make it flat and smooth.

[0100] B. Fine leveling: After the initial setting, use fine leveling to make sure there is no trace on the surface. After the final setting of the concrete pouring, the concrete is cured: watering curing, plastic film covering curing.

[0101] In addition, the above-mentioned bull leg trolley needs to meet the following requirements.

[0102] 1.1 Panel force calculation

[0103] 1. Material parameters

[0104] The panel is made of steel with a thickness of 6mm; the bottom support is made of 8# channel steel;

[0105] Panel elastic modulus E(N / mm 2 ): 210000; Panel bending strength design value (N / mm 2 ): 205;

[0106] The joist material is: 12# channel steel;

[0107] 2. Template panel calculation

[0108] The formwork panel is a bending member, and its bending strength and rigidity are verified according to the three-span continuous beam;

[0109] The section inertia moment I and section resistance moment W of the formwork panel are:

[0110] W=120×0.6 2 / 6=7.2cm 3 ;

[0111] I=120×0.6 3 / 12=2.16cm 4 ;

[0112] The formwork panels are calculated as continuous beams.

[0113] 3. Load calculation

[0114] (1) The static load is the deadweight of the reinforced concrete slab and formwork panel (kN / m):

[0115] q 1 =24×0.46×1.2+3×1.2=16.848kN / m;

[0116] (2) Live load refers to the load of construction personnel and equipment (kN / m):

[0117] q 2 =3×1.2=3.6kN / m;

[0118] 4. Strength calculation

[0119] The calculation formula is as follows:

[0120] M=0.1ql 2

[0121] Where: q = 1.2 × 16.848 + 1.4 × 3.6 = 25.258 kN / m;

[0122] Maximum bending moment M = 0.1 × 25.258 × 380 2 =364725.52N·mm;

[0123] Calculated value of maximum stress of panel σ=M / W=364725.52 / 7200=50.65N / mm 2 ;

[0124] Design value of panel bending strength [f] = 205N / m 2 ;

[0125] The maximum stress calculated value of the panel is 50.65N / m 2 Less than the panel's design bending strength of 205N / mm 2 , meeting the requirements.

[0126] 4. Deflection calculation

[0127] The deflection calculation formula is:

[0128] ν=0.677q1 4 / (100EI)≤[ν]=1 / 250;

[0129] where q = q 1 =16.848kN / m,

[0130] The calculated value of the maximum deflection of the panel is v = 0.677 × 16.848 × 380 4 / (100×210000×2.16×10 4 )=0.524mm;

[0131] Maximum allowable deflection of the panel [v] = 380 / 250 = 1.52 mm;

[0132] The calculated maximum deflection value of the panel, 0.524 mm, is less than the maximum allowable deflection of the panel, 1.52 mm, and meets the requirements.

[0133] 1.2 Middle layer support verification

[0134] 1. Middle support load conditions

[0135] The loads borne by the bracket mainly include: the deadweight of cast-in-place corbel concrete, the deadweight of formwork and accessories, and construction live loads.

[0136] (1) Concrete deadweight: 24kN / m 3 ;

[0137] (2) Standard steel formwork: 3kN / m 2 ;

[0138] (3) Construction load: 3kN / m 2 .

[0139] 2. Strength and rigidity requirements of construction supports

[0140] When checking the rigidity of the construction support, its deformation value shall not exceed the following values:

[0141] The elastic deflection of the rods that bend after the support is loaded shall not be greater than 1 / 400 of the corresponding structural span;

[0142] The tensile and compressive stress of Q235 steel is σ≤205Mpa.

[0143] 3. Load calculation

[0144] (1) Scaffolding secondary rib verification:

[0145] The secondary ribs are made of 8# channel steel with a spacing of 280mm and a span of 1200m.

[0146] Table 1.2-1 Main rib material properties

[0147]

[0148] Maximum load acting on 8# channel steel:

[0149] a The self-weight of concrete is 24kN / m 3 × 0.46m (plate thickness) × 0.28m (load bearing width of a single 8# channel steel) = 3.09kN / m;

[0150] b Panel load is 3kN / m 2 ×0.28m=0.84kN / m;

[0151] c Structural support construction load 3kN / m 2 ×0.28m=0.84kN / m;

[0152] Then q 1 =(a+b+c)×1.2m=(3.09+0.84+0.84)×1.2kN / m=5.724kN / m.

[0153] Strength verification:

[0154] The maximum bending moment of the main beam is M max =0.125q max l 2 / 10=0.125×5.724×0.28 2 / 10=0.0561KN.m;

[0155] Maximum bending stress σmax=M max / W=0.0561KN.m / 25300mm 3 =2.22N / mm 2 ≤205N / mm 2 ;

[0156] Therefore, the strength meets the requirements.

[0157] Deflection Calculation

[0158] W max =5q 1 l 4 / 384EI=5×5.724×1200 4 / (384×206000×1010000)=0.74mm≤[w]=l / 400=3mm,

[0159] Therefore, the secondary 8# channel steel meets the requirements.

[0160] (2) Calculation of the main rib of the bracket (80mm I-beam):

[0161] The main ribs are made of 12# channel steel, with a maximum spacing of 650mm and a maximum span of 1200m.

[0162] Table 1. 2-2 Main rib material properties

[0163]

[0164] Maximum load acting on 12# channel steel:

[0165] a The self-weight of concrete is 24kN / m 3 × 0.46m (plate thickness) × 0.65m (load bearing width of a single 12# channel steel) = 7.18kN / m;

[0166] b Panel load is 3kN / m 2 ×0.9m=2.7kN / m;

[0167] c Structural support construction load 3kN / m 2 ×0.9m=2.7kN / m;

[0168] Then q 1 =(a+b+c)×1.2m=(7.18+2.7+2.7)×1.2kN / m=15.096kN / m.

[0169] Strength verification:

[0170] The maximum bending moment of the main beam is M max =0.125q max l 2 / 10=0.125×15.096×0.65 2 / 10=0.08KN.m;

[0171] Maximum bending stress σmax=M max / W=0.08KN.m / 62100mm 3 =1.29N / mm 2 ≤205N / mm 2 ;

[0172] Therefore, the strength meets the requirements.

[0173] Deflection Calculation

[0174] W max =5q 1 l 4 / 384EI=5×15.096×1200 4 / (384×206000×3910000)=0.506mm≤[w]=l / 400=3mm,

[0175] Therefore, 12# channel steel is used for the main rib to meet the requirements.

[0176] (3) Bracket verification

[0177] Stability calculation formula of the vertical pole: (120*120*5mm square tube frame)

[0178] Where:

[0179] N---Design value of axial pressure of the vertical pole (kN);

[0180] φ --- Stability coefficient of axially compressed members, which is taken from Appendix D of the code according to the slenderness ratio λ;

[0181] λ——slenderness ratio, given by Sure;

[0182] i——Calculate the cross-sectional radius of gyration of the vertical pole 33.03mm;

[0183] A——Net cross-sectional area of ​​the pole (mm 2 )2300mm;

[0184] l 0 ——Calculated length of the pole (m); l 0 =h+2a;

[0185] h——pole spacing, take h=1.71m;

[0186] a——The length of the vertical pole extending out of the top horizontal pole, a=0.12m;

[0187] [f]----Design value of compressive strength of steel pipe uprights: [f] = 205N / mm 2 ;

[0188] Therefore:

[0189] Calculated length of the pole: l 0 =1.71+2×0.12=1.95m;

[0190] Pole slenderness ratio

[0191] By checking the appendix of "Safety Technical Regulations for Socket-Type and Spigot-Type Steel Pipe Supports in Construction", we can get the stability coefficient of the vertical pole φ=0.362.

[0192]

[0193] σ<[f];

[0194] The stability of the pole meets the requirements.

[0195] 1.3 Bottom beam verification:

[0196] The bottom beam adopts HN400*200H steel box beam with a maximum spacing of 650mm and a maximum span of 1300m.

[0197] Table 1. 3-1 Main rib material properties

[0198]

[0199] Maximum load acting on HN400*200 box beam:

[0200] Then q1 = (12.5 + 15.096 + 4.63 + 10 + 4.42) × 1.3m = 60.6kN / m;

[0201] Strength verification:

[0202] The maximum bending moment of the main beam is Mmax = 0.125qmax12 / 10 = 0.125 × 60.6 × 0.652 / 10 = 0.32 KN.m;

[0203] Maximum bending stress σmax=Mmax / W=0.32KN.m / 1435000mm3=0.21N / mm2≤205N / mm2;

[0204] Therefore, the strength meets the requirements.

[0205] Deflection Calculation

[0206] Wmax=5q114 / 384EI=5×60.6×13004 / (384×206000×287020000)=0.038mm≤[w]=l / 400=3mm, so the main rib uses HN400*200 box girder to meet the requirements.

[0207] The above detailed description of the present invention is intended to enable persons familiar with the art to understand the contents of the present invention and implement them. It does not limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. An integrated casting system for the inner wall panels and top brackets of an ultra-large diameter tunnel. It is characterized in that It comprises: a trolley, which comprises a base, a frame located on the base, and a walking component arranged at the bottom of the base and capable of switching between a walking mode and a positioning mode in a tunnel; A top corbel casting module is located at the top of the vehicle frame and at one side of the vehicle frame in the length direction, and the top corbel casting module includes a corbel bracket arranged on the vehicle frame in a relatively movable manner, and a corbel template arranged on the corbel bracket, wherein the corbel bracket can be extended and retracted up and down and move close to or away from the tunnel segment, close to form a casting cavity, and away from demoulding; the corbel bracket includes a plurality of struts arranged in a stacked and intersecting manner, wherein the top surfaces of the plurality of struts constitute a supporting surface, and the corbel template includes a plurality of assembled templates assembled side by side and erected on the supporting surface; the assembled template includes a first template located at the bottom and extending horizontally from the inside to the outside, a second template extending obliquely upward from the inner end of the first template, and a third template assembled and assembled on the upper end of the second template in a horizontally rotating manner, and the plurality of struts are respectively supported at the bottom of the first template and the second template; A wall panel casting module is located below the same side as the top corbel casting module, and the wall panel casting module includes a bottom support frame extending outward from the bottom of a frame, an arm frame whose lower end is rotated and slidably arranged on the outer end of the bottom support frame, a wall formwork arranged on the outside of the arm frame, an external part detachably connected to the embedded part through a connector, and a telescopic support rod arranged between the arm frame and the frame, wherein during the telescopic movement of the telescopic support rod, the lower end of the arm frame is used as the movement center to move close to the tunnel segment to form a casting cavity or away from the demolding, there are multiple bottom support frames and they are arranged side by side along the length direction of the frame, the arm frame and the bottom support frame are arranged one by one, and the wall formwork is composed of multiple pieces spliced ​​together, wherein the multiple wall formworks are fixedly connected to the arm frame by multiple connecting rods.

2. The integrated casting system for inner wall panels and top brackets of super-large diameter tunnels according to claim 1, Features: The multiple support rods include a first rod and a second rod respectively extending along the length and width directions of the frame, and a third rod inclined from bottom to top, wherein the multiple first rods and the multiple second rods are respectively laid flat at intervals, and the multiple first rods are respectively erected on the multiple second rods, the first template intersects with the first rods and is erected on a supporting surface formed by the tops of the multiple first rods, and the upper end of the third rod is supported on the bottom of the second template.

3. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 1, Features: The top corbel casting module also includes a lifting component, a transverse component, and a flipping component, wherein the lifting component includes a plurality of lifting rods extending in the up-and-down directions and telescopically moving synchronously, the transverse component includes a plurality of transverse rods extending in the width direction of the frame and telescopically moving synchronously, and the flipping component includes a single flipping shaft that crosses the connection between the third template and the second template, wherein the third template rotates relative to the second template during the forward and reverse rotation of the flipping shaft.

4. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 1, Features: The bottom support frame includes a first support rod extending from top to bottom and from inside to outside, and a second support rod extending horizontally from the outer end of the first support rod. The arm frame includes a first arm rod arranged parallel to the wall formwork, and a second arm rod bent inward from the lower end of the first arm rod. The lower end of the second arm rod is connected to the outer end of the second support rod by sliding and rotation in the horizontal direction.

5. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 4, Features: The connecting rod is vertically arranged with the first arm rod, and a reinforcing rod is also arranged on the first support rod, wherein the reinforcing rod comprises a first reinforcing rod fixed on the vehicle frame and the first arm rod, and a second reinforcing rod obliquely supported between the first reinforcing rod and the first arm rod.

6. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 5, Features: A platform bracket is also provided on the upper part of each first arm, and the platform bracket and the first arm form a tripod rod of a right triangle. The platform bracket also includes an extension rod extending upward from the end of the tripod rod away from the first arm.

7. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 6, Features: The telescopic struts are arranged in one-to-one correspondence with the first arm rods, and at least two telescopic struts are arranged between each of the first arm rods and the second reinforcing rods, wherein the movement of the telescopic struts can drive the first arm rods to relatively flip and horizontally move around the lower end.

8. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 1, Features: The frame is stacked up and down and has at least two layers.

9. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 1, Features: The walking components include multiple sets of walking wheels located at the bottom of the base, and support legs arranged on the base and capable of being extended up and down, wherein the support legs are supported on the tunnel walking surface and enable the walking wheels to be separated from the tunnel walking surface to position the frame.

10. The integrated casting system for inner wall panels and top brackets of a super-large diameter tunnel according to claim 1, Features: A guardrail is also provided on the top layer of the frame.

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