Asynchronous construction method for concrete cross beam with wave-shaped steel web of pylon

Abstract

The application provides a cable tower corrugated steel web concrete beam asynchronous construction method, which adopts an asynchronous construction method that tower body construction does not stop, a hydraulic climbing formwork continues to construct the tower body after the beam, and another team is arranged to construct the beam. Compared with the tower beam synchronous construction method of the prior art, the asynchronous construction method can reduce the stagnation time of the main tower hydraulic climbing formwork, so that the construction period is shortened. Meanwhile, the cable tower corrugated steel web concrete beam asynchronous construction method adopts a hanging frame structure composed of a load-bearing portal fixed to the top of the corrugated steel web and side pull rods, middle pull rods and connecting pull rods connected with the load-bearing portal to support the formwork for casting in place of the bottom plate and the top plate of the beam, so as to replace the traditional K-type support method and the box-in-disk buckle cast-in-place method. The construction method is more convenient and the steel consumption is less, so that the construction cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of bridge construction equipment technology, specifically to an asynchronous construction method for a corrugated steel web concrete crossbeam of a cable tower. Background Technology

[0002] Traditional cable tower crossbeam construction primarily involves the integrated construction of the tower and crossbeam, specifically the use of hydraulic climbing formwork for tower limb construction. Once the hydraulic climbing formwork reaches the crossbeam position and the support frame and formwork are installed, the tower limb and crossbeam are poured with concrete together. While this method improves the construction quality of the interface between the tower and crossbeam, it also faces challenges such as prolonged hydraulic climbing formwork stagnation and conflicts between the cast-in-place crossbeam support frame and the hydraulic climbing formwork.

[0003] With the development of suspension bridge design, steel-concrete composite beams are gradually replacing traditional reinforced concrete prestressed beams. If tower and beam construction is carried out simultaneously, after the K-type support and corrugated steel web are installed, the top and bottom slabs need to be cast in place and subsequent prestressing construction is required. At this time, the hydraulic climbing formwork of the main tower will be idle for a longer period of time, which is not conducive to the overall control of the construction period.

[0004] Meanwhile, the traditional K-type scaffolding method for constructing corrugated steel web concrete beams requires first installing the corrugated steel web, then casting the base slab, followed by prestressing the base slab, erecting a disc-lock scaffold inside the box girder, and finally casting the top slab concrete. This method means that the K-type scaffold supports need to be dismantled under the beam, and these supports are often made of large-sized steel sections, which violates the safety principle of reducing the installation and dismantling of large-sized steel sections at height. Moreover, cutting and reusing large-sized steel sections is not conducive to ensuring the quality of subsequent steel scaffolding installation, and the construction process is time-consuming. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems mentioned in the background art above, and provides an asynchronous construction method for corrugated steel web concrete beams of cable towers, which can shorten the construction period while reducing construction risks.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for asynchronous construction of the corrugated steel web concrete crossbeam of a cable tower involves using hydraulic climbing formwork to construct the tower legs. Once the hydraulic climbing formwork has risen to a position where its bottom platform is higher than the designed position of the crossbeam, another construction team is assigned to construct the crossbeam, allowing the tower legs and crossbeam to be constructed independently and synchronously. The crossbeam construction method includes the following steps: S1, after the hydraulic climbing formwork climbs to the point where the bottom platform of the hydraulic climbing formwork is higher than the design position of the crossbeam, a construction platform for the construction of the crossbeam is installed below the design position of the crossbeam. S2, The two sets of corrugated steel webs of the crossbeam are installed using a cantilever assembly method, with the two sets of corrugated steel webs being arranged at relative intervals. S3, a plurality of load-bearing gantry frames are installed on the top of the corrugated steel web. The plurality of load-bearing gantry frames are spaced apart along the length of the corrugated steel web. Each load-bearing gantry frame connects the top of two sets of corrugated steel webs. Adjacent load-bearing gantry frames are connected by transverse connectors. S4, using a tower crane to install several pairs of side tie rods on the load-bearing gantry. The several pairs of side tie rods are spaced apart along the length direction of the corrugated steel web. Each pair of side tie rods is installed on opposite sides of the load-bearing gantry, so that the two sets of corrugated steel webs are located between a pair of side tie rods on opposite sides of the load-bearing gantry. S5, the bottom formwork for the construction of the crossbeam bottom plate is transported to the construction platform in sections by a tower crane for assembly. Several support back ribs are installed on the bottom surface of the assembled bottom formwork corresponding to several pairs of side tie rods. The support back ribs are spaced apart along the length direction of the corrugated steel web. The bottom formwork is lifted as a whole by the tower crane so that the end of the side tie rod away from the load-bearing portal is fixed after passing through the corresponding support back rib. S6. Install the central tie rod, which is located between the two sets of corrugated steel webs. The top of the central tie rod is connected to the load-bearing gantry, and the bottom of the central tie rod is fixed after passing through the bottom formwork and the corresponding support back rib. The central tie rod 70 is covered with a pre-embedded PVC pipe. Install the bottom plate side formwork for the construction of the crossbeam bottom plate, and then pour the bottom plate concrete in the space formed by the bottom formwork and the bottom plate side formwork. After the concrete strength meets the design requirements, prestressing is performed to complete the in-situ pouring construction of the bottom plate. Then, remove the bottom formwork, side tie rods and central tie rod. S7. Using a tower crane, the back ribs of the top plate used for the construction of the crossbeam top plate are hoisted between the two sets of corrugated steel webs, so that the opposite sides of the back ribs of the top plate are connected to the top of the two sets of corrugated steel webs respectively. Then, the inner formwork of the top plate used for the construction of the crossbeam top plate is laid on the top surface of the back ribs of the top plate, and then the side formwork of the top plate used for the construction of the crossbeam top plate is installed. The concrete of the top plate is poured in place in the space formed by the inner formwork of the top plate, the side formwork of the top plate, and the two sets of corrugated steel webs. After the concrete strength meets the design requirements, prestressing is performed. Then, the part of the load-bearing gantry that protrudes outside the top plate is cut off, and the concrete finishing work at the cut-off position is done. This completes the asynchronous construction of the corrugated steel web concrete crossbeam.

[0007] Furthermore, in step S5, two sets of support plates are laid on several of the support back ribs. The two sets of support plates are respectively located at the opposite ends of the support back ribs to form a bottom plate construction channel. Each set of support plates is located between the end of the support back rib and the side tie rod on the corresponding side. In step S6, bottom plate side formwork for crossbeam bottom plate construction is installed on the bottom plate construction channel.

[0008] Furthermore, the central tie rod is arranged in several rows, and the several rows of central tie rods are spaced apart along the length direction of the corrugated steel web.

[0009] Furthermore, support plates are laid on the top of several load-bearing gantry frames to form a top plate construction channel. In step S7, workers install the top plate back rib, top plate inner mold and top plate side mold on the top plate construction channel.

[0010] Furthermore, the load-bearing gantry includes several columns, load-bearing beams, and two diagonal braces. The bottom ends of the columns are respectively fixed to the tops of the two sets of corrugated steel webs. The load-bearing beams are fixedly connected to the tops of the columns. The two diagonal braces are respectively connected to the columns fixed to the two sets of corrugated steel webs. One end of the diagonal brace is fixedly connected to the innermost column, and the other end is fixedly connected to the load-bearing beam. The transverse connectors are fixedly connected to the columns of two adjacent load-bearing gantry frames. The tops of the side tie rods and the middle tie rods are both fixed to the load-bearing beams. The support plate is laid on the top surface of the load-bearing beams of the load-bearing gantry frames.

[0011] Furthermore, in step S6, the bottom formwork is dismantled using a hand-operated hoist, and then the dismantled bottom formwork, the supporting back rib, and the bottom plate side formwork are hoisted to the bottom of the tower for recycling.

[0012] Furthermore, during the dismantling of the bottom formwork, firstly, hand-operated hoists are installed on opposite sides of the load-bearing beam. Then, the hand-operated hoists on opposite sides of the load-bearing beam are connected to both ends of the supporting back rib via steel wire ropes. Subsequently, the connection between the side tie rods and the middle tie rod and the supporting back rib is released. Finally, by operating the hand-operated hoists, the bottom formwork, the supporting back rib, and the bottom plate side formwork are moved downwards together to complete the demolding. Finally, the connection between the steel wire rope and the supporting back rib is released, and the bottom formwork, the supporting back rib, and the bottom plate side formwork are hoisted to the bottom of the main tower for recovery.

[0013] Furthermore, in step S7, the top plate back rib is connected to the load-bearing gantry by several connecting rods, and the connecting rods are fitted with pre-embedded PVC pipes.

[0014] By adopting the above technical solution, the present invention has the following beneficial effects: The aforementioned asynchronous construction method for the corrugated steel web concrete crossbeams of cable towers involves continuous tower construction, with hydraulic climbing formwork passing the crossbeams and tower construction continuing while another team works on the crossbeams. Compared to existing synchronous tower-beam construction methods, this reduces the downtime of the main tower's hydraulic climbing formwork, thus shortening the construction period. Furthermore, this asynchronous construction method utilizes a load-bearing gantry fixed to the top of the corrugated steel web, along with a suspension structure consisting of side tie rods, central tie rods, and connecting tie rods connected to the gantry, to support the cast-in-place formwork of the bottom and top slabs of the crossbeams. This replaces the traditional K-type scaffolding method and the box girder casting method, making the construction more convenient, requiring less steel, and reducing construction costs.

[0015] The aforementioned asynchronous construction method for corrugated steel web concrete crossbeams of cable towers utilizes a construction platform at the bottom of the crossbeam and a load-bearing gantry at the top of the corrugated steel web. Tower cranes are used to gradually install the formwork for the bottom and top slabs of the crossbeam. The construction platform is relatively lightweight, allowing components such as connecting beams and Bailey beams to be lowered as a whole and then assembled piece by piece using a winch. In contrast, the traditional K-type scaffolding method requires disassembling the scaffolding piece by piece in mid-air, especially lowering each distribution beam individually to the ground. This assembly becomes increasingly dangerous with increasing height. Therefore, the aforementioned asynchronous construction method for corrugated steel web concrete crossbeams of cable towers avoids the high risks associated with the mid-air installation and disassembly of large steel scaffolding and the difficulty in controlling processing quality due to the repeated cutting and reuse of steel sections. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure after the installation of the construction platform in the asynchronous construction method of the corrugated steel web concrete beam of the cable tower according to a preferred embodiment of the present invention.

[0017] Figure 2 for Figure 1 The diagram shows the cross-sectional structure of the construction platform.

[0018] Figure 3 This is a schematic diagram of the installation of the corrugated steel web of the crossbeam in the asynchronous construction method of the corrugated steel web concrete crossbeam of the cable tower in a preferred embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram of the installation of the load-bearing gantry in the asynchronous construction method of the corrugated steel web concrete beam of the cable tower according to a preferred embodiment of the present invention.

[0020] Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure.

[0021] Figure 6 This is a schematic diagram of the installation of the side tie rods in the asynchronous construction method of the corrugated steel web concrete beam of the cable tower according to a preferred embodiment of the present invention.

[0022] Figure 7 for Figure 6 A schematic diagram of the cross-sectional structure.

[0023] Figure 8 for Figure 7 This is a structural diagram after the middle tie rod has been installed.

[0024] Figure 9 This is a schematic diagram illustrating the installation of the top slab cast-in-place formwork for the crossbeam in the asynchronous construction method of the corrugated steel web concrete crossbeam of the cable tower, according to a preferred embodiment of the present invention.

[0025] Figure 10 for Figure 9 A schematic diagram of the cross-sectional structure.

[0026] Figure 11 This is a schematic diagram of the structure after the construction of the crossbeam is completed using the asynchronous construction method of the corrugated steel web concrete crossbeam of the cable tower, which is a preferred embodiment of the present invention.

[0027] Figure 12 for Figure 11 A schematic diagram of the cross-sectional structure.

[0028] Key component marking instructions 10. Construction platform; 11. Connecting bracket; 110. Convex strip; 12. Connecting beam; 13. Bailey beam; 14. Steel scaffolding; 15. First tie rod; 16. Second tie rod; 17. First guardrail; 18. Horizontal brace; 30. Load-bearing gantry; 31. Column; 32. Load-bearing beam; 33. Diagonal brace; 35. Horizontal connector; 36. Support plate; 37. Second guardrail; 40. Side tie rod; 41. Top nut; 42. Bottom nut; 50. Bottom formwork; 51. Support back rib; 60. Support plate; 61. Third guardrail; 70. Middle tie rod; 71. Upper nut; 73. Lower nut; 91. Top plate back rib; 92. Top plate inner formwork; 94. Connecting tie rod; 95. First nut; 96. Second nut; 200. Main tower; 210. Tower leg; 300. Crossbeam; 310. Corrugated steel web; 311. Embedded section; 312. Cantilever assembly; 313. Cantilever section; 400. Bottom plate; 500. Top plate. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0032] Please see Figure 1 and Figure 3 A preferred embodiment of the present invention provides an asynchronous construction method for the corrugated steel web concrete crossbeam of a cable tower, which employs a hydraulic climbing formwork (not shown) to construct the tower leg 210 of the main tower 200. Once the hydraulic climbing formwork has climbed to a point where its bottom platform is higher than the designed position of the crossbeam 300, another construction team is assigned to construct the crossbeam 300, allowing the tower leg 210 and the crossbeam 300 to be constructed independently and synchronously. The construction method for the crossbeam 300 includes the following steps: S1, after the hydraulic climbing formwork has climbed to the point where the bottom platform of the hydraulic climbing formwork is higher than the design position of the crossbeam 300, a construction platform 10 for the construction of the crossbeam 300 is installed below the design position of the crossbeam 300.

[0033] After the hydraulic climbing formwork has risen to a point where its bottom platform is higher than the designed position of the crossbeam 300, a construction platform 10 for the construction of the crossbeam 300 is then installed below the designed position of the crossbeam 300 to avoid conflict between the construction platform 10 and the hydraulic climbing formwork. Please refer to [further details omitted]. Figure 2In this embodiment, the construction platform 10 includes a plurality of connecting brackets 11 spaced apart on the tower body, a plurality of connecting beams 12 fixedly connected to the plurality of connecting brackets 11 and spaced apart, a plurality of sets of Bailey beams 13 spaced apart on the plurality of connecting beams 12, and a plurality of steel scaffolding planks 14 laid on top of the plurality of sets of Bailey beams 13. In this embodiment, the plurality of connecting brackets 11 are spaced apart on the tower body along the longitudinal direction of the bridge. Specifically, a fixing box (not shown) is pre-embedded in the tower body during the tower body pouring. The bottom of the connecting bracket 11 has a protruding strip 110, and the bottom of the connecting bracket 11 is inserted into the fixing box through the protruding strip 110. The top of the connecting bracket 11 is connected to the tower body through a first tie rod 15. The plurality of connecting beams 12 are spaced apart along the transverse direction of the bridge, and each connecting beam 12 is fixedly connected to the plurality of connecting brackets 11. In this embodiment, adjacent connecting brackets 11 are also connected by a horizontal bracing 18, which connects the plurality of connecting brackets 11 into a whole to enhance the overall stability. The top of the Bailey beam 13 is connected to the main tower 200 via a second tie rod 16 to enhance its stability. Several steel planks 14 are laid on top of several sets of Bailey beams 13 to form an operating platform. In this embodiment, first guardrails 17 are also provided on opposite sides of the operating platform.

[0034] S2, please refer to the above as well. Figure 3 The two sets of corrugated steel webs 310 of the crossbeam 300 are installed using a cantilever assembly method, with the two sets of corrugated steel webs 310 arranged at intervals relative to each other. Specifically, the corrugated steel web 310 includes two embedded sections 311 and two cantilever assemblies 312 that connect the two embedded sections 311 respectively. The cantilever assemblies 312 include a plurality of cantilever segments 313 arranged sequentially along the length of the crossbeam 300. Step S2 includes the following steps: S21, during the pouring of the main tower 200, the pre-embedded section 311 of the corrugated steel web 310 is constructed, and the hydraulic climbing formwork used for the construction of the main tower 200 is lifted to a designated position above the pre-embedded section 311.

[0035] S22, the cantilever section 313 is lifted by a tower crane. After being lifted into position, the first cantilever section 313 is connected to the embedded section 311. The cantilever assembly of the remaining cantilever sections 313 of the corrugated steel web 310 continues. During assembly, the cantilever section 313 is connected to the tower crane, and then lifted into position. After being lifted into position, the cantilever section 313 is connected to the previous cantilever section 313 until the two cantilever assemblies 312 are joined. When bolting adjacent cantilever sections 313, temporary fixing is first done using punch pins. Then, a welding platform is installed at the connection point of the adjacent cantilever sections 313 to install the joint bolts. After the joint bolts are installed, the joint is welded.

[0036] S3, please refer to the above as well. Figure 4 and Figure 5Several load-bearing gantry frames 30 are installed on the top of the corrugated steel web 310. The load-bearing gantry frames 30 are spaced apart along the length of the corrugated steel web 310. Each load-bearing gantry frame 30 connects the top of two sets of corrugated steel webs 310. Adjacent load-bearing gantry frames 30 are connected by transverse connectors 35.

[0037] In this embodiment, the load-bearing gantry 30 includes several columns 31, load-bearing beams 32, and two diagonal braces 33. The bottom ends of the columns 31 are respectively fixed to the tops of two sets of corrugated steel webs 310. The load-bearing beams 32 are fixedly connected to the tops of the columns 31. The two diagonal braces 33 are respectively connected to the columns 31 fixed to the two sets of corrugated steel webs 310. One end of the diagonal brace 33 is fixedly connected to the innermost column 31, that is, the column 31 closest to the other corrugated steel web 310, and the other end of the diagonal brace 33 is fixedly connected to the load-bearing beam 32. A transverse connector 35 is fixedly connected to the columns 31 of two adjacent load-bearing gantry 30s. In this embodiment, the transverse connector 35 is made of structural steel. A support plate 36 is also laid on the top of the load-bearing beams 32 to form a top plate construction channel for the construction of the top plate 500 of the crossbeams 300. Specifically, the support plate 36 is laid on the top surface of the load-bearing beams 32 of the several load-bearing gantry 30s. A second guardrail 37 is also installed on both sides of the top slab construction passage to further improve safety.

[0038] S4, please refer to the above as well. Figure 6 and Figure 7 A number of pairs of side tie rods 40 are installed on the load-bearing gantry 30 using a tower crane. The pairs of side tie rods 40 are spaced apart along the length of the corrugated steel web 310. Each pair of side tie rods 40 is installed on opposite sides of the load-bearing gantry 30, so that the two sets of corrugated steel webs 310 are located between the side tie rods 40 on opposite sides of the load-bearing gantry 30.

[0039] In this embodiment, the top end of the side tie rod 40 is connected to the load-bearing beam 32. Specifically, the side tie rod 40 is a threaded steel bar. The load-bearing beam 32 is provided with a first lifting hole (not shown) corresponding to the side tie rod 40. The side tie rod 40 passes through the corresponding first lifting hole. The top end of the side tie rod 40 is threadedly connected to a top nut 41. The top nut 41 is supported on the load-bearing beam 32 to connect the side tie rod 40 and the load-bearing beam 32 together.

[0040] S5. Using a tower crane, the bottom formwork 50 for the construction of the crossbeam 300 and the base plate 400 is transported in sections to the construction platform 10 for assembly. Several pairs of side tie rods 40 are installed on the bottom surface of the assembled bottom formwork 50, and several support back ribs 51 are set at intervals along the length of the corrugated steel web 310. The bottom formwork 50 is lifted as a whole by the tower crane, so that the end of the side tie rod 40 away from the load-bearing gantry 30 is fixed after passing through the corresponding support back rib 51.

[0041] In this embodiment, the bottom formwork 50 used for the construction of the crossbeam 300 and the base plate 400 is hoisted in sections to the operating platform of the construction platform 10 for assembly. The bottom end of the side tie rod 40 is connected to the support back rib 51. Specifically, the two ends of the support back rib 51 are provided with second lifting holes (not shown) corresponding to the side tie rod 40. The side tie rod 40 passes through the corresponding second lifting holes (not shown). The bottom end of the side tie rod 40 is threadedly connected to a bottom nut 42. The bottom nut 42 abuts against the bottom surface of the support back rib 51 to connect the side tie rod 40 and the support back rib 51 together.

[0042] In this embodiment, two sets of support plates 60 are laid on several supporting back ribs 51. The two sets of support plates 60 are respectively located at opposite ends of the supporting back ribs 51 to form a base plate construction channel. Each set of support plates 60 is located between the end of the supporting back rib 51 and the corresponding side tie rod 40. A third guardrail 61 is fixed on the side of the base plate construction channel away from the side tie rod 40 to further improve construction safety.

[0043] S6, please refer to the above as well. Figure 8 The middle tie rod 70 is installed between two sets of corrugated steel webs 310. The top of the middle tie rod 70 is connected to the load-bearing gantry 30. The bottom end of the middle tie rod 70 is fixed after passing through the bottom formwork 50 and the corresponding support back rib 51. The middle tie rod 70 is covered with a pre-embedded PVC pipe (not shown in the figure). The bottom plate side formwork (not shown in the figure) for the construction of the crossbeam 300 and the bottom plate 400 is installed. Then, the concrete of the bottom plate 400 is poured in the space formed by the bottom formwork 50 and the bottom plate side formwork. After the concrete strength meets the design requirements, prestressing is performed to complete the in-situ construction of the bottom plate 400. Then, the bottom formwork 50, the side tie rods 40 and the middle tie rod 70 are removed.

[0044] In this embodiment, several rows of central tie rods 70 are arranged at intervals along the length of the corrugated steel web 310. The top end of the central tie rod 70 is connected to the load-bearing beam 32. Specifically, the central tie rod 70 is a threaded steel bar, and the load-bearing beam 32 has a first connecting hole (not shown) corresponding to the central tie rod 70. The central tie rod 70 passes through the corresponding first connecting hole, and the top end of the central tie rod 70 is threadedly connected to an upper nut 71. The upper nut 71 is supported on the load-bearing beam 32 to connect the central tie rod 70 and the load-bearing beam 32 together. The bottom end of the middle tie rod 70 is connected and fixed after the bottom mold 50 and the support back rib 51 are inserted. Specifically, the two ends of the support back rib 51 are provided with second connecting holes (not shown) corresponding to the side tie rods 40, and the bottom mold 50 is provided with through holes (not shown) corresponding to the middle tie rod 70. The middle tie rod 70 is inserted through the corresponding through holes and the second connecting holes. The bottom end of the middle tie rod 70 is threaded with a lower nut 73, which abuts against the bottom surface of the support back rib 51 to fix the middle tie rod 70.

[0045] In this embodiment, bottom plate side molds are fixed at opposite ends of the bottom mold 50. The two bottom plate side molds and the bottom mold 50 together enclose a space for the in-situ pouring of the bottom plate 400 concrete. The structure of the bottom mold 50 and the bottom plate side molds, as well as the connection method between the bottom plate side molds and the bottom mold 50, are prior art and will not be described in detail here for brevity. During the installation of the bottom plate side molds, workers install the bottom plate side molds for the construction of the crossbeam 300 bottom plate on the bottom plate construction passage supporting the back rib 51.

[0046] In this embodiment, a hand-operated hoist (not shown) is used to dismantle the bottom formwork 50, and the bottom formwork 50, supporting back rib 51, and bottom plate side formwork are hoisted to the bottom of the tower for recovery. Specifically, when dismantling the bottom formwork 50, firstly, hand-operated hoists are installed on opposite sides of the load-bearing beam 32, and the hand-operated hoists on opposite sides of the load-bearing beam 32 are connected to the opposite ends of the supporting back rib 51 via steel wire ropes; then, the connection between the side tie rod 40 and the middle tie rod 70 and the supporting back rib 51 is released, that is, the lower nut 73 is removed from the middle tie rod 70, and the bottom nut 42 is removed from the bottom end of the side tie rod 40; finally, by operating the hand-operated hoist, the bottom formwork 50, supporting back rib 51, and bottom plate side formwork move downwards together to complete demolding; finally, the connection between the steel wire rope and the supporting back rib 51 is released, and the bottom formwork 50, supporting back rib 51, and bottom plate side formwork are hoisted to the bottom of the main tower 200 for recovery.

[0047] When removing the side tie rod 40, the top nut 41 can be unscrewed from the side tie rod 40, and then the side tie rod 40 can be pulled away from the load-bearing gantry 30. The central tie rod 70 is fitted with a pre-embedded PVC pipe, which isolates the concrete of the base slab 400 from the central tie rod 70 during the pouring process, facilitating its subsequent removal. Specifically, the pre-embedded PVC pipe is fitted into the middle portion of the central tie rod 70, located between the upper nut 71 and the lower nut 73. When removing the central tie rod 70, the upper nut 71 can be unscrewed from the central tie rod 70, and then the central tie rod 70 can be pulled away from the load-bearing gantry 30. After the side tie rods 40 and the central tie rod 70 are removed, they are hoisted to the base of the main tower 200 for recovery.

[0048] S7, please refer to the above as well. Figures 9 to 12Using a tower crane, the back rib 91 of the top plate for the construction of the crossbeam 300 and the top plate 500 is lifted to the space between the two sets of corrugated steel webs 310, so that the opposite sides of the back rib 91 are connected to the top of the two sets of corrugated steel webs 310 respectively. Then, the inner formwork 92 of the top plate for the construction of the crossbeam 300 and the top plate 500 is laid on the top surface of the back rib 91, and then the side formwork of the top plate for the construction of the crossbeam 300 and the top plate 500 is installed. The concrete of the top plate 500 is poured in place in the space formed by the inner formwork 92, the side formwork, and the two sets of corrugated steel webs 310. After the concrete strength meets the design requirements, prestressing is performed. Then, the part of the load-bearing gantry 30 that protrudes outside the top plate is cut off, and the concrete at the cut-off position is finished. This completes the asynchronous construction of the corrugated steel web 310 concrete crossbeam 300.

[0049] In this embodiment, workers install the roof slab back rib 91, the roof slab inner formwork 92, and the roof slab side formwork on the roof slab construction passage. The opposite sides of the roof slab back rib 91 are respectively connected to the top of two sets of corrugated steel webs 310, and the roof slab back rib 91 is connected to the load-bearing gantry 30 via connecting rods 94. The connecting rods 94 are fitted with pre-embedded PVC pipes. Specifically, the connecting rods 94 are vertically arranged, with their opposite ends passing through the roof slab back rib 91 and the load-bearing beams 32 of the load-bearing gantry 30, respectively. The top end of the connecting rod 94 is threaded with a first nut 95, which supports the top surface of the load-bearing beam 32; the bottom end of the connecting rod 94 is threaded with a second nut 96, which abuts against the bottom surface of the roof slab back rib 91. An embedded PVC pipe is fitted into the middle part of the connecting rod 94 between the first nut 95 and the second nut 96. This is used to isolate the concrete from the connecting rod 94 when the top plate 500 is poured, and to facilitate the disassembly of the connecting rod 94.

[0050] The inner mold 92 of the top plate includes secondary ribs (not shown) and bamboo plywood panels (not shown). During installation, several secondary ribs are first laid on the back ribs 91 of the top plate, and then bamboo plywood panels are laid on the top surface of the secondary ribs to form the inner mold 92 of the top plate. A top plate side mold is installed on the outer side of each set of corrugated steel webs 310 away from the other set of corrugated steel webs 310. Several columns 31 of the load-bearing gantry 30 are located between the top plate side molds on the two sets of corrugated steel webs 310.

[0051] In step S7, after the cast-in-place construction of the top slab 500 is completed, the connecting tie rod 94 is removed. When removing the connecting tie rod 94, the first nut 95 and the second nut 96 can be unscrewed from the connecting tie rod 94, and then the connecting tie rod 94 can be pulled away from the load-bearing gantry 30. Subsequently, the top slab back rib 91, the top slab inner mold 92, and the top slab side mold are removed to complete the demolding. Afterward, the part of the load-bearing gantry 30 protruding outside the top slab 500 is cut off. The removed connecting tie rod 94, top slab back rib 91, top slab inner mold 92, and top slab side mold are hoisted to the bottom of the main tower 200 for recycling.

[0052] The aforementioned asynchronous construction method for the corrugated steel web concrete crossbeam of the cable tower employs a method where tower construction continues uninterrupted, with hydraulic climbing formwork passing through the crossbeam 300 and tower construction continuing while another team works on the crossbeam 300. Compared to existing synchronous tower-beam construction methods, this reduces the downtime of the hydraulic climbing formwork on the main tower 200, thereby shortening the construction period. Furthermore, this asynchronous construction method utilizes a scaffold structure consisting of a load-bearing gantry 30 fixed to the top of the corrugated steel web 310, side tie rods 40, central tie rods 70, and connecting tie rods 94 connected to the load-bearing gantry 30 to support the cast-in-place formwork of the bottom plate 400 and top plate 500 of the crossbeam 300. This replaces the traditional K-type scaffolding method and the box girder casting method, making the construction method more convenient, requiring less steel, and reducing construction costs.

[0053] The above-mentioned asynchronous construction method for the corrugated steel web concrete beam of the cable tower involves installing the side tie rods 40, the middle tie rods 70, and the connecting tie rods 94 on the load-bearing gantry 30. This not only ensures that the corrugated steel web 310 is subjected to uniform stress and reduces the probability of deformation, but also allows for the simultaneous installation of the inner formwork 92 of the top slab, thereby enabling the cast-in-place construction of the top slab 500 without installing the inner disc fasteners.

[0054] The above-mentioned asynchronous construction method for the corrugated steel web concrete crossbeam of the cable tower uses a construction platform 10 set at the bottom of the crossbeam 300 and a load-bearing gantry 30 installed on the top of the corrugated steel web 310. The formwork for the bottom plate 400 and top plate 500 of the crossbeam 300 is gradually installed using a tower crane. Compared with the traditional K-type support method, this method avoids the high risk of installing and dismantling large steel supports in the air and the problem of difficult quality control caused by the repeated cutting and reuse of steel sections.

[0055] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for asynchronous construction of corrugated steel web concrete beams for cable towers, characterized in that, The main tower legs are constructed using hydraulic climbing formwork. Once the hydraulic climbing formwork has climbed to a point where its bottom platform is higher than the designed position of the crossbeam, another construction team is assigned to construct the crossbeam, allowing the tower legs and crossbeam to be constructed independently and synchronously. The construction method for the crossbeam includes the following steps: S1, after the hydraulic climbing formwork has climbed to the point where the bottom platform of the hydraulic climbing formwork is higher than the design position of the crossbeam, a construction platform for the construction of the crossbeam is installed below the design position of the crossbeam. S2, The two sets of corrugated steel webs of the crossbeam are installed using a cantilever assembly method, with the two sets of corrugated steel webs being arranged at relative intervals. S3, a plurality of load-bearing gantry frames are installed on the top of the corrugated steel web. The plurality of load-bearing gantry frames are spaced apart along the length of the corrugated steel web. Each load-bearing gantry frame connects the top of two sets of corrugated steel webs. Adjacent load-bearing gantry frames are connected by transverse connectors. S4, using a tower crane to install several pairs of side tie rods on the load-bearing gantry. The several pairs of side tie rods are spaced apart along the length direction of the corrugated steel web. Each pair of side tie rods is installed on opposite sides of the load-bearing gantry, so that the two sets of corrugated steel webs are located between a pair of side tie rods on opposite sides of the load-bearing gantry. S5, the bottom formwork for the construction of the crossbeam bottom plate is transported to the construction platform in sections by a tower crane for assembly. Several support back ribs are installed on the bottom surface of the assembled bottom formwork corresponding to several pairs of side tie rods. The support back ribs are spaced apart along the length direction of the corrugated steel web. The bottom formwork is lifted as a whole by the tower crane so that the end of the side tie rod away from the load-bearing portal is fixed after passing through the corresponding support back rib. S6. Install the central tie rod, which is located between the two sets of corrugated steel webs. The top of the central tie rod is connected to the load-bearing gantry, and the bottom of the central tie rod is fixed after passing through the bottom formwork and the corresponding support back rib. The central tie rod is fitted with a pre-embedded PVC pipe. Install the bottom plate side formwork for the construction of the crossbeam bottom plate, and then pour the bottom plate concrete in the space formed by the bottom formwork and the bottom plate side formwork. After the concrete strength meets the design requirements, prestressing is performed to complete the in-situ pouring of the bottom plate. Then, remove the bottom formwork, side tie rods and central tie rod. S7. Using a tower crane, the back ribs of the top plate used for the construction of the crossbeam top plate are hoisted between the two sets of corrugated steel webs, so that the opposite sides of the back ribs of the top plate are connected to the top of the two sets of corrugated steel webs respectively. Then, the inner formwork of the top plate used for the construction of the crossbeam top plate is laid on the top surface of the back ribs of the top plate, and then the side formwork of the top plate used for the construction of the crossbeam top plate is installed. The concrete of the top plate is poured in place in the space formed by the inner formwork of the top plate, the side formwork of the top plate, and the two sets of corrugated steel webs. After the concrete strength meets the design requirements, prestressing is performed. Then, the part of the load-bearing gantry that protrudes outside the top plate is cut off, and the concrete finishing work at the cut-off position is done. This completes the asynchronous construction of the corrugated steel web concrete crossbeam.

2. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 1, characterized in that, In step S5, two sets of support plates are laid on several of the support back ribs. The two sets of support plates are respectively located at the opposite ends of the support back ribs to form a bottom plate construction channel. Each set of support plates is located between the end of the support back rib and the side tie rod on the corresponding side. In step S6, bottom plate side formwork for crossbeam bottom plate construction is installed on the bottom plate construction channel.

3. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 1, characterized in that, The central tie rod is arranged in several rows, and the several rows of central tie rods are spaced apart along the length direction of the corrugated steel web.

4. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 1, characterized in that, In step S7, support plates are laid on the top of several load-bearing gantry frames to form a top plate construction channel. Workers install the top plate back ribs, top plate inner molds, and top plate side molds on the top plate construction channel.

5. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 4, characterized in that, The load-bearing gantry includes several columns, load-bearing beams, and two diagonal braces. The bottom ends of the columns are respectively fixed to the tops of two sets of corrugated steel webs. The load-bearing beams are fixedly connected to the tops of the columns. The two diagonal braces are respectively connected to the columns fixed to the two sets of corrugated steel webs. One end of the diagonal brace is fixedly connected to the innermost column, and the other end is fixedly connected to the load-bearing beam. The transverse connectors are fixedly connected to the columns of two adjacent load-bearing gantry frames. The tops of the side tie rods and the middle tie rods are both fixed to the load-bearing beams. The support plate is laid on the top surface of the load-bearing beams of the load-bearing gantry frames.

6. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 5, characterized in that, In step S6, the bottom formwork is removed using a hand-operated hoist, and then the removed bottom formwork, the supporting back rib, and the bottom plate side formwork are hoisted to the bottom of the tower for recycling.

7. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 6, characterized in that, When dismantling the bottom formwork, firstly, hand-operated hoists are installed on opposite sides of the load-bearing beam. Then, the hand-operated hoists on opposite sides of the load-bearing beam are connected to both ends of the supporting back rib via steel wire ropes. Subsequently, the connection between the side tie rods and the middle tie rod and the supporting back rib is released. Finally, by operating the hand-operated hoists, the bottom formwork, the supporting back rib, and the bottom plate side formwork are moved downwards together to complete the demolding. Finally, the connection between the steel wire rope and the supporting back rib is released, and the bottom formwork, the supporting back rib, and the bottom plate side formwork are hoisted to the bottom of the main tower for recovery.

8. The asynchronous construction method for the corrugated steel web concrete beam of the cable tower as described in claim 1, characterized in that, In step S7, the top plate back rib is connected to the load-bearing gantry by several connecting rods, and the connecting rods are fitted with pre-embedded PVC pipes.

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