Built-in hydraulic lifting creeping formwork construction method for hollow pier of extra-large cable bent tower bridge

Abstract

The invention relates to a built-in hydraulic lifting creeping formwork construction method for an extra-large cable tower bridge hollow pier, and belongs to the technical field of creeping formworks. Comprising the following steps: S1, determining the position of a pier body; s2, scabbling the top surface of the base; s3, the side wall of the first-section hollow pier is poured; s4, a hydraulic creeping formwork system is assembled; s5, the inner formwork and the outer formwork are hoisted; s6, outer formwork modules are installed, then assembled backward moving devices are hoisted to the top face of a hydraulic creeping formwork system through a tower crane and connected with the outer formworks, positioning mechanisms are arranged between every two adjacent outer formworks, and the four outer formworks are enclosed through the positioning mechanisms and tightly attached to the outer side wall of the first section of hollow pier; s7, an inner formwork module is assembled; s8, closing the mold and pouring; s9, creeping formwork construction is conducted; s10, circulating construction is conducted; the problems that in a hollow pier built-in creeping formwork construction method, the construction precision of the hollow pier wall is low, and the construction efficiency is low are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of climbing formwork, and in particular relates to a construction method of a built-in hydraulic lifting climbing formwork for a hollow pier of an extra-large cable tower bridge. Background Art

[0002] With the continuous development and progress of bridge construction, the demand for extra-large cable tower bridges is increasing. Traditional construction methods are difficult to meet the construction progress and quality requirements. Therefore, new technical means need to be introduced to improve construction efficiency and quality. The application of hydraulic climbing formwork technology has gradually developed in this context. It provides a more efficient and reliable construction method for the construction of extra-large cable tower bridges. Hydraulic climbing formwork technology is a commonly used technology in bridge construction. It is mainly used for the construction of extra-large hollow piers. Hydraulic climbing formwork technology uses a hydraulic system to realize the lifting and movement of the formwork support frame to meet the construction needs of different heights and positions.

[0003] During the current construction of extra-large hollow pier walls, the operating platform inside the hollow thin-walled pier needs to be erected from the bottom of the hollow thin-walled pier, and then the operating platform is installed on the frame. During the construction process, every time the hollow thin-walled pier is raised by one section, it is necessary to continue to erect the frame on the upper end of the original frame to make the height of the operating platform inside the hollow thin-walled pier adapt to the construction height of the hollow thin-walled pier.

[0004] In the cast-in-place construction of super-high piers, the outer formwork can be replaced by hydraulic climbing formwork technology, but the inner formwork has multiple disadvantages during the construction process, such as large material usage, high construction cost, long construction period, high foundation requirements, low construction efficiency, and high risks. Therefore, how to choose a more reasonable construction method to achieve the quality and safety indicators of super-high piers, ensure the construction period requirements, and minimize construction errors is a technical problem that needs to be solved in construction. Summary of the invention

[0005] In order to solve the above-mentioned problems existing in the prior art, the present invention provides a method for constructing a built-in hydraulic lifting climbing formwork for the hollow pier of an extra-large cable-tower bridge, which solves the problem that the formwork is replaced many times and the wear caused by the cumbersome disassembly and assembly in the built-in climbing formwork construction method of the hollow pier greatly reduces the flatness of the formwork, thereby affecting the construction accuracy of the hollow pier wall and reducing the construction efficiency.

[0006] The purpose of the present invention can be achieved by the following technical solution: A method for constructing a hollow pier with a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork, comprising the following steps:

[0007] S1: Determine the position of the pier body. Use the total station to determine the four points around the pier body and use them to determine the center position of the pier body, ensuring that the error range is less than ±5mm;

[0008] S2: roughening the top surface of the base, roughening the joint surface of the top surface of the base;

[0009] S3: Cast the first section of the hollow pier side wall, tie the first section of steel bars, hoist the outer formwork for the first time, then cast concrete in the outer formwork to form the first section of the hollow pier side wall, and then install the embedded mechanism at the preset position of the hollow pier side wall;

[0010] S4: Assemble the hydraulic climbing formwork system, assemble the external load-bearing tripod and truss, connect the hanging seat body, external hanging platform, external load-bearing tripod, truss, external guide rail and hydraulic system to the outside of the side wall of the base, and fix them through the embedded mechanism;

[0011] S5: hoist the inner formwork and the outer formwork, tie the steel bars on the top surface of the base, use the tower crane to hoist the inner formwork to the preset position, and hoist the outer formwork on the top surface of the hydraulic climbing formwork system for the second time;

[0012] S6: Install the outer formwork module, and then use the tower crane to hoist the assembled rearward moving device to the top surface of the hydraulic climbing formwork system and connect it to the outer formwork. Positioning mechanisms are respectively set between the four adjacent outer formworks, and the four outer formworks are enclosed and fastened to the outer wall of the first hollow pier through the positioning mechanisms;

[0013] S7: Assemble the inner formwork module, assemble the prefabricated inner formwork truss, inner load-bearing tripod, inner lifting platform and inner guide rail. After the assembly is completed, it is hoisted by a tower crane and connected to the inner formwork and fixed to the inner side of the side wall of the first hollow pier through the embedded parts system;

[0014] S8: Close the mold and pour, pour concrete between the inner and outer formwork to form the side wall of the first section of the hollow pier, and demould the inner and outer formwork after pouring;

[0015] S9: Climbing formwork construction, the outer guide rail is climbed to the preset position and fixed, the hydraulic system drives the outer formwork module to climb to the preset position through the outer guide rail, and at the same time the inner formwork module is climbed to the same height position of the outer formwork module through the tower crane, and then the inner and outer formworks are combined to form the casting area of ​​the next section of the hollow pier side wall, and the first section of the hollow pier side wall is formed by casting in the casting area;

[0016] S10: Circular construction, circulate construction steps S8-S9, and cast the side walls of the hollow pier in sequence.

[0017] As a preferred technical solution of the present invention, in step S2, cutting is performed before roughening the top surface of the base, and the roughening depth is such that 1 / 3 to 1 / 2 of the stones on the old concrete need to be exposed.

[0018] As a preferred technical solution of the present invention, a plurality of connecting rods are provided on the top surfaces of the inner formwork module and the outer formwork module, and the plurality of connecting rods connect the inner formwork module and the outer formwork module to form a whole. An inner guide rail climbing mechanism is provided in the inner formwork truss of the inner formwork module, and the inner guide rail climbing mechanism is used to climb the inner guide rail to the same position as the outer guide rail in the hydraulic climbing system.

[0019] As a preferred technical solution of the present invention, the embedded part mechanism includes a wall attachment device, a climbing cone, mounting bolts, an embedded part plate and high-strength bolts, the two ends of the high-strength bolts are respectively connected to the embedded part plate and the climbing cone, the mounting bolts are connected to the other end of the climbing cone, the wall attachment device is installed on the side wall of the hollow pier through the climbing cone, and the hydraulic climbing formwork system is fixed to the side wall of the hollow pier through the wall attachment device.

[0020] As a preferred technical solution of the present invention, the external load-bearing tripod is installed at the bottom of the truss and is used to improve the supporting force of the hydraulic climbing formwork system.

[0021] As a preferred technical solution of the present invention, the positioning mechanism includes a channel steel back rib, a plurality of wooden I-beams, two inclined seats, a fixed inclined rod and two tightening screws. A plurality of wooden I-beams are placed on the channel steel back rib and fixed by connecting claw bolts. The outer formwork is connected to the plurality of wooden I-beams. Two inclined seats are respectively installed at both ends of the channel steel back rib. The four outer formworks are enclosed to form a rectangle that fits the side wall of the first hollow pier. The two inclined seats of adjacent channel steel back ribs are connected by fixed inclined rods and tightening screws so that the outer formwork fits tightly to the side wall of the first hollow pier.

[0022] As a preferred technical solution of the present invention, in step S7, the concrete to be poured is centrally mixed by a concrete processing plant and delivered to the pouring point via a concrete delivery pump.

[0023] As a preferred technical solution of the present invention, the outer formwork and the inner formwork are both formed by large steel formworks.

[0024] As a preferred technical solution of the present invention, in step S7, the pier body is watered before the formwork is removed after the concrete is poured, so as to keep the pier body always in a moist state.

[0025] The beneficial effects of the present invention are:

[0026] 1. By setting a positioning mechanism on the outer template module to ensure the accuracy of the outer template during the mold closing process, the outer template can fit tightly on the side wall of the hollow pier that has been constructed. The side wall of the hollow pier that has been constructed is used as the positioning reference to ensure that the verticality of each section of the hollow pier side wall in the subsequent construction will not accumulate errors as the construction height gradually increases, thereby ensuring that the linear gradient accuracy of the hollow thin-walled pier can be accurately controlled;

[0027] 2. During the continuous construction process, the outer formwork module climbs through the hydraulic climbing formwork system to form the outer formwork of the next section of the hollow pier side wall, while the inner formwork of the hollow pier is moved to the same height as the outer formwork module by hoisting the inner formwork module by the tower crane to form the inner formwork of the hollow pier, and then the inner and outer formwork modules are combined to form a casting area, and the side wall of the hollow pier is formed by pouring concrete in the casting area, thereby avoiding the situation where the inner formwork module needs to continue to set up the frame at the upper end of the original frame every time the hollow thin-walled pier is raised by one section, reducing the situation where the inner formwork occupies a lot of materials during the construction process, reducing construction costs, and shortening construction period, solving the problem of frequent template replacements and wear caused by cumbersome disassembly and assembly in the built-in climbing formwork construction method of hollow piers, greatly reducing the flatness of the template, thereby affecting the construction accuracy of the hollow pier wall and reducing construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0029] Figure 1 It is a flow chart of the construction method of the present invention;

[0030] Figure 2 This is a schematic diagram of the installation of the inner and outer templates of the present invention;

[0031] Figure 3 This is a schematic diagram of the hollow section concrete pouring of the present invention;

[0032] Figure 4 It is a structural schematic diagram of the hydraulic climbing formwork system of the present invention;

[0033] Figure 5 It is a schematic diagram of the structure of the embedded parts mechanism of the present invention;

[0034] Figure 6 It is a schematic diagram of the positioning mechanism structure of the present invention;

[0035] Main component symbols

[0036] In the figure: 1. pier body; 2. embedded parts mechanism; 21. climbing cone; 22. mounting bolts; 23. embedded parts plate; 24. high-strength bolts; 25. wall attachment device; 3. hydraulic climbing formwork system; 31. external load-bearing tripod; 32. truss; 33. hanging seat body; 34. external hanging platform; 35. external guide rail; 4. internal formwork; 41. internal formwork truss; 42. internal load-bearing tripod; 43. internal hanging platform; 44. internal guide rail; 5. external formwork; 6. backward moving device; 7. positioning mechanism; 71. channel steel back rib; 72. wooden I-beam; 73. inclined seat; 74. fixed inclined rod; 75. tightening screw; 76. connecting claw bolt; 8. connecting rod. DETAILED DESCRIPTION

[0037] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0038] See also Figure 1-Figure 6 This embodiment provides a method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork, comprising the following steps:

[0039] S1: Determine the position of pier 1. Use the total station to determine the four points around pier 1 and use them to determine the center of pier 1. Fix the laser vertical instrument on the ground control point and strictly align, fix and level it to ensure the construction accuracy in the subsequent construction process and ensure that the error range is less than ±5mm;

[0040] S2: Roughen the top surface of the base, roughen the joint surface of the top surface of the base to ensure that the pier body 1 concrete is tightly connected with the cap;

[0041] S3: Cast the first section of the hollow pier side wall, tie the first section of steel bars, hoist the outer formwork 5 for the first time, then cast concrete in the outer formwork 5 to form the first section of the hollow pier side wall, and then install the embedded mechanism 2 at the preset position of the hollow pier side wall;

[0042] S4: Assemble the hydraulic climbing formwork system 3, assemble the external load-bearing tripod 31 and the truss 32, connect the hanging seat 33, the external hanging platform 34, the external load-bearing tripod 31, the truss 32, the external guide rail 35 and the hydraulic system to the outside of the side wall of the base, and fix them through the embedded mechanism 2;

[0043] S5: hoist the inner formwork 4 and the outer formwork 5, tie the steel bars on the top surface of the base, use the tower crane to hoist the inner formwork 4 to the preset position, and hoist the outer formwork 5 on the top surface of the hydraulic climbing formwork system 3 for the second time;

[0044] S6: The outer formwork 5 modules are installed, and then the assembled rearward moving devices 6 are hoisted to the top surface of the hydraulic climbing formwork system 3 by a tower crane and connected to the outer formwork 5, and positioning mechanisms 7 are respectively set between the four adjacent outer formworks 5, and the four outer formworks 5 are enclosed by the positioning mechanisms 7 to form a closed area, and the bottoms of the four outer formworks 5 are fastened and attached to the outer wall of the first hollow pier;

[0045] S7: Assemble the inner formwork 4 module, assemble the prefabricated inner formwork truss 41, the inner load-bearing tripod 42, the inner hanging platform 43 and the inner guide rail 44, and after the assembly is completed, hoist it through a tower crane and connect it to the inner formwork 4, and then fix it to the inner side of the side wall of the first hollow pier through an embedded system;

[0046] S8: close the mold and pour concrete between the inner and outer templates 5 to form the side wall of the first hollow pier. After the pouring is completed, the inner and outer templates 5 are demoulded;

[0047] S9: Climbing formwork construction, the outer guide rail 35 is climbed to the preset position and fixed, the hydraulic system drives the outer formwork 5 module to climb to the preset position through the outer guide rail 35, and at the same time, the inner formwork 4 module is climbed to the same height position of the outer formwork 5 module through the tower crane, and then the inner and outer formworks 5 are combined to form the casting area of ​​the next section of the hollow pier side wall, and the first section of the hollow pier side wall is formed by casting in the casting area;

[0048] S10: Circular construction, circulate construction steps S8-S9, and cast the side walls of the hollow pier in sequence.

[0049] During the construction of the hollow pier of the extra-large cable tower bridge, the outer formwork 5 modules and the inner formwork 4 modules are overlapped on the inner and outer side walls of the hollow pier, and the inner and outer formwork 5 modules are combined to form a casting area for the side wall of the hollow pier, and the side wall of the hollow pier is formed by pouring concrete in the casting area. At the same time, during the continuous construction process, the outer formwork 5 modules are climbed by the hydraulic climbing formwork system 3 to form the outer formwork 5 of the next section of the hollow pier side wall, and the inner formwork 4 of the hollow pier is moved to the same height as the outer formwork 5 modules by hoisting the inner formwork 4 modules by the tower crane to form the inner formwork 4 of the hollow pier, and then the inner and outer formwork 5 modules are combined to form a casting area, and the side wall of the hollow pier is formed by pouring concrete in the casting area, thereby avoiding the situation that the inner formwork 4 modules need to continue to set up the frame at the upper end of the original frame every time the hollow thin-walled pier is raised by one section, reducing the situation that the inner formwork 4 occupies a lot of materials during the construction process, reducing the construction cost, and shortening the construction period.

[0050] In the cast-in-place construction of the super-high pier body 1, as the pier body 1 is raised, the verticality of the pier body 1 and the accuracy of the linear gradient of the pier 1 are required to be higher. Moreover, as the construction height continues to increase, it is necessary to avoid the accumulation of errors that may affect the structure of the pier body 1.

[0051] By setting a positioning mechanism 7 on the outer template 5 module to ensure the accuracy of the outer template 5 during the mold closing process, the outer template 5 can fit tightly on the completed hollow pier side wall, and the completed hollow pier side wall is used as a positioning reference to ensure that the verticality of each section of the hollow pier side wall in subsequent construction will not have cumulative errors as the construction height gradually increases, thereby ensuring that the accuracy of the linear gradient of the hollow thin-walled pier can be accurately controlled.

[0052] Since the inner formwork 4 modules need to be hoisted by a tower crane during the climbing process, hoisting the inner formwork 4 modules by a tower crane will not only increase the risk of high-altitude operations as the construction height increases, but also reduce construction efficiency.

[0053] Therefore, in order to ensure the stability of the inner formwork 4 module during the construction process and improve the construction efficiency, a plurality of connecting rods 8 are provided on the top surface of the inner formwork 4 module and the top surface of the outer formwork 5 module. The plurality of connecting rods 8 connect the inner formwork 4 module and the outer formwork 5 module to form a whole. When the connecting rods 8 are engaged with the inner formwork 4 module, an inner guide climbing mechanism is provided in the inner form truss 41 of the inner formwork 4 module. During the construction of the next section of the hollow pier side wall, the connecting rods 8 are disconnected from the inner formwork 4 module, and the outer formwork 5 module passes through the liquid normally. The hydraulic climbing system climbs, and when the outer formwork 5 module is in the preset position, the inner formwork 4 module is connected to the tower crane, and the tower crane is used to support the inner formwork 4 module. Then the inner guide rail climbing mechanism climbs the inner guide rail 44 to the same position as the outer guide rail 35 in the hydraulic climbing system, and then the tower crane lifts the inner formwork 4 module to the preset position through the sliding guide of the guide rail, and then fixes it through the connecting rod 8 to ensure that the inner formwork 4 module can remain stable during the construction process and reduce construction errors to cast the next section of the hollow pier side wall.

[0054] By adopting the same guide rail climbing system as the hydraulic climbing system in the inner template 4 module to climb the inner guide rail 44, there is no need to climb the remaining components of the inner template 4. Therefore, the output force required for the inner guide rail climbing mechanism to climb can be greatly reduced, thereby reducing the size of the hydraulic device in the climbing mechanism, thereby reducing production costs and facilitating installation.

[0055] In order to further ensure that the side wall of the hollow pier can be well bonded to the base when pouring, and to ensure the strength of the pier body 1 after construction, in this embodiment, in step S2, a tangent is made before roughening the top surface of the base, and the roughening depth is 1 / 3 to 1 / 2 of the stones on the old concrete need to be exposed. The roughening process can increase the roughness of the concrete surface, thereby enhancing the mechanical bite force between the new concrete and the old concrete. When the stones are exposed to a certain depth, a larger contact area can be formed, which helps to improve the bonding effect, and the exposed 1 / 3 to 1 / 2 roughening depth can prevent peeling and falling off caused by the shrinkage of the newly poured concrete or other factors. If the roughening depth is insufficient, it may cause the bond between the new and old concrete to be loose, forming gaps, thereby affecting the bonding force between the newly poured concrete and the old concrete.

[0056] During the cyclic climbing process of the hydraulic climbing formwork system 3, it is necessary to connect the hydraulic climbing formwork system 3 with the embedded parts system in turn to keep it fixed, so that the guide rails and the outer formwork 5 modules can climb in turn to complete the construction process of the hollow pier side wall. Therefore, in order to ensure the stability of the hydraulic climbing formwork system 3 during the climbing process, in one embodiment, the embedded parts mechanism 2 includes a wall attachment device 25, a climbing cone 21, a mounting bolt 22, an embedded parts plate 23 and a high-strength bolt 24, the two ends of the high-strength bolt 24 are respectively connected to the embedded parts plate 23 and the climbing cone 21, the mounting bolt 22 is connected to the other end of the climbing cone 21, the wall attachment device 25 is installed on the side wall of the hollow pier through the climbing cone 21, the hydraulic climbing formwork system 3 is fixed to the side wall of the hollow pier through the wall attachment device 25, and the embedded parts are fixed to the side wall of the hollow pier through the embedded parts. When installing the mechanism 2, fix the climbing cone 21 to the formwork with the mounting bolts 22, apply butter to the hole of the climbing cone 21 and tighten the high-strength screw to ensure that concrete cannot flow into the thread of the climbing cone 21, and screw the embedded plate 23 on the other end of the high-strength bolt 24, with the cone facing the formwork, in the opposite direction of the climbing cone 21. When the above components are installed, install the wall attachment device 25 at the position corresponding to the climbing cone 21 on the side wall of the hollow pier, and then fix the hydraulic climbing formwork system 3 on the side wall of the hollow pier through the wall attachment device 25, thereby completing the pouring and other construction steps. The wall attachment device 25 can be consistent with the wall attachment device 25 in the existing hydraulic climbing formwork system 3, as long as it can provide a stable connection effect for the hydraulic climbing formwork system 3, and it is not too limited here.

[0057] In order to better ensure the stability of the outer formwork 5 module during the mold closing and rearward movement process, in one embodiment, the external load-bearing tripod 31 is installed at the bottom of the truss 32 and is used to improve the supporting force of the hydraulic climbing formwork system 3. The outer formwork 5 and the rearward movement device 6 are both installed on the top surface of the hydraulic climbing formwork system 3. Therefore, the supporting force of the hydraulic climbing formwork system 3 is improved by the external load-bearing tripod 31. The entire hydraulic climbing formwork system 3 is composed of a hanger body 33, an external hanging platform 34, an external load-bearing tripod 31, a truss 32, a guide rail and a hydraulic system. Therefore, the truss 32 is the main load-bearing structure of the entire climbing formwork system. The external load-bearing tripod 31 is installed at the bottom of the truss 32 to improve the supporting force of the truss 32, thereby improving the stability of the outer formwork 5 during mold closing and demoulding and rearward movement.

[0058] Since the side walls of the hollow pier need to ensure that their verticality is within a preset range during the construction process, and the side walls of the hollow pier are constructed layer by layer, it is necessary to ensure the construction accuracy of each layer during the construction process to avoid the cumulative error caused by the continuous increase in construction height affecting the construction quality. Therefore, in order to ensure that the hollow pier will not be affected by the cumulative error during the construction process, in one embodiment, the positioning mechanism 7 includes a channel steel back rib 71, a plurality of wooden I-beams 72, two inclined seats 73, a fixed inclined rod 74 and two tightening screws 75. A plurality of wooden I-beams 72 are placed on the channel steel back rib 71 and fixed by connecting claw bolts 76. The outer formwork 5 is connected to the plurality of wooden I-beams 72. Two inclined seats 73 are respectively installed at both ends of the channel steel back rib 71. The four outer formworks 5 are enclosed to form a rectangle that fits the side wall of the first section of the hollow pier. The two inclined seats 73 of the adjacent channel steel back ribs 71 are connected by fixed inclined rods 74 and tightening screws 75 so that the outer formwork 5 fits tightly to the first section. When the outer formwork 5 is hoisted again, it is necessary to ensure that the outer formwork 5 will not affect the construction quality due to the cumulative error when the subsequent continuous mold closing construction forms the hollow pier side walls. Therefore, when the outer formwork 5 is hoisted to the top surface of the hydraulic climbing formwork system 3, a positioning mechanism 7 is installed on each outer formwork 5. When the outer formwork 5 is enclosed on the side wall of the first hollow pier, the inclined seat 73 of the channel steel back rib 71 in the two adjacent outer formworks 5 will be connected by fixing the inclined rod 74, and then tightened and fixed by the tightening screw 75, so as to ensure that the outer formwork 5 can be tightly fitted on the side wall of the hollow pier, and then the retreat device is connected to the outer formwork 5, so that when the subsequent retreat device drives the outer formwork 5 to close the mold, the mold closing accuracy can be guaranteed, and the hollow pier side wall that has been constructed is used as the positioning reference, so as to ensure that the verticality of each hollow pier side wall of the subsequent construction will not cause cumulative errors in the hollow pier side wall as the construction height gradually increases.

[0059] In order to better improve the construction efficiency, in one embodiment, in step S7, the concrete to be poured is centrally mixed by a concrete processing plant and delivered to the pouring point via a concrete delivery pump. When pouring, the concrete is first mixed in advance and then poured directly, which reduces the mixing time and improves the construction efficiency.

[0060] In order to avoid wear on the surface of the template during frequent demoulding, which greatly reduces the flatness of the template, in one embodiment, the outer template 5 and the inner template 4 are both made of large-block steel templates. The large-block steel templates have strong wear resistance and can withstand multiple uses without deformation or damage. This can significantly extend the service life of the template. The use of large-block templates can reduce splicing and the number of gaps, which helps to avoid leakage of concrete during pouring and also helps to improve the overall strength and density of the concrete.

[0061] During the climbing formwork construction, the climbing process can only be carried out after the cast hollow pier side wall reaches the preset strength. Therefore, in order to improve the construction effect, in one embodiment, in step S7, the pier body 1 after the concrete is cast is watered and maintained before the formwork is removed to keep the pier body 1 always in a moist state. Concrete will generate hydration heat during the hardening process. Watering can effectively control the temperature increase, reduce the temperature gradient, and reduce cracks caused by temperature changes. In addition, the hydration process of cement requires a certain amount of water. Watering can provide sufficient water to ensure that the cement is fully hydrated, thereby improving the comprehensive performance of the concrete. At the same time, the concrete can solidify faster and reach the preset strength, thereby improving the construction efficiency.

[0062] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for constructing a hollow pier with a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork, characterized in that: The following steps are involved: S1: Determine the position of the pier body. Use the total station to determine the four points around the pier body and use them to determine the center position of the pier body, ensuring that the error range is less than ±5mm; S2: roughening the top surface of the base, roughening the joint surface of the top surface of the base; S3: Cast the first section of the hollow pier side wall, tie the first section of steel bars, hoist the outer formwork for the first time, then cast concrete in the outer formwork to form the first section of the hollow pier side wall, and then install the embedded mechanism at the preset position of the hollow pier side wall; S4: Assemble the hydraulic climbing formwork system, assemble the external load-bearing tripod and truss, connect the hanging seat body, external hanging platform, external load-bearing tripod, truss, external guide rail and hydraulic system to the outside of the side wall of the base, and fix them through the embedded mechanism; S5: hoist the inner formwork and the outer formwork, tie the steel bars on the top surface of the base, use the tower crane to hoist the inner formwork to the preset position, and hoist the outer formwork on the top surface of the hydraulic climbing formwork system for the second time; S6: Install the outer formwork module, and then use the tower crane to hoist the assembled rearward moving device to the top surface of the hydraulic climbing formwork system and connect it to the outer formwork. Positioning mechanisms are respectively set between the four adjacent outer formworks, and the four outer formworks are enclosed and fastened to the outer wall of the first hollow pier through the positioning mechanisms; S7: Assemble the inner formwork module, assemble the prefabricated inner formwork truss, inner load-bearing tripod, inner lifting platform and inner guide rail. After the assembly is completed, it is hoisted by a tower crane and connected to the inner formwork and fixed to the inner side of the side wall of the first hollow pier through the embedded parts system; S8: Close the mold and pour, pour concrete between the inner and outer formwork to form the side wall of the first section of the hollow pier, and demould the inner and outer formwork after pouring; S9: Climbing formwork construction, the outer guide rail is climbed to the preset position and fixed, the hydraulic system drives the outer formwork module to climb to the preset position through the outer guide rail, and at the same time the inner formwork module is climbed to the same height position of the outer formwork module through the tower crane, and then the inner and outer formworks are combined to form the casting area of ​​the next section of the hollow pier side wall, and the first section of the hollow pier side wall is formed by casting in the casting area; S10: Circular construction, circulate construction steps S8-S9, and cast the side walls of the hollow pier in sequence.

2. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: A plurality of connecting rods are provided on the top surfaces of the inner formwork module and the outer formwork module, and the plurality of connecting rods connect the inner formwork module and the outer formwork module to form a whole. An inner guide rail climbing mechanism is provided in the inner formwork truss of the inner formwork module, and the inner guide rail climbing mechanism is used to climb the inner guide rail to the same position as the outer guide rail in the hydraulic climbing system.

3. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: In step S2, the top surface of the base is cut before roughening, and the roughening depth is such that 1 / 3 to 1 / 2 of the stones on the old concrete need to be exposed.

4. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: The embedded part mechanism includes a wall attachment device, a climbing cone, mounting bolts, an embedded part plate and high-strength bolts, the two ends of the high-strength bolts are respectively connected to the embedded part plate and the climbing cone, the mounting bolts are connected to the other end of the climbing cone, the wall attachment device is installed on the side wall of the hollow pier through the climbing cone, and the hydraulic climbing formwork system is fixed to the side wall of the hollow pier through the wall attachment device.

5. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: The external load-bearing tripod is installed at the bottom of the truss and is used to improve the supporting force of the hydraulic climbing formwork system.

6. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: The positioning mechanism includes a channel steel back rib, a plurality of wooden I-beams, two inclined brackets, a fixed inclined rod and two tightening screws. A plurality of wooden I-beams are placed on the channel steel back rib and fixed by connecting claw bolts. The outer formwork is connected to the plurality of wooden I-beams. Two inclined brackets are respectively installed at both ends of the channel steel back rib. The four outer formworks are enclosed to form a rectangle that fits the side wall of the first hollow pier. The two inclined brackets of adjacent channel steel back ribs are connected by fixed inclined rods and tightening screws so that the outer formwork fits tightly to the side wall of the first hollow pier.

7. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: In step S7, the concrete to be poured is centrally mixed by a concrete processing plant and delivered to the pouring point via a concrete delivery pump.

8. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: The outer formwork and the inner formwork are both made of large steel formworks.

9. The method for constructing a hollow pier of a super-large cable tower bridge with a built-in hydraulic lifting climbing formwork according to claim 1, characterized in that: In step S7, the pier body is watered and maintained after pouring the concrete before demolding to keep the pier body always moist.

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