Cable-stayed bridge cantilever precast slab laying method and cable-stayed bridge structure

Abstract

The application discloses a cable-stayed bridge cantilever prefabricated plate laying method and a cable-stayed bridge structure, and relates to the field of cable-stayed bridge construction. The cable-stayed bridge cantilever prefabricated plate laying method comprises the following steps: keeping the top longitudinal beam above a target steel truss beam in a disconnected state, arranging a temporary support below the separation of the top longitudinal beam, and laying prefabricated plates above all the steel truss beams; hoisting the target steel truss beam and the prefabricated plates above the adjacent steel truss beams of the target steel truss beam, lifting a lifting support point located on the top of an auxiliary pier to support the target steel truss beam, connecting the top longitudinal beam above the target steel truss beam, and removing the temporary support; placing the hoisted prefabricated plates to the original positions, wet-connecting all the adjacent prefabricated plates, and replacing the lifting support point with a formal support; wherein the target steel truss beam is a steel truss beam located above an auxiliary pier. The overall rigidity of the structure is improved when the prefabricated plates are laid, and the construction risk is reduced.

Description

Technical Field

[0001] This invention relates to the field of cable-stayed bridge construction, specifically to a method for laying cantilever precast slabs for cable-stayed bridges and a cable-stayed bridge structure. Background Technology

[0002] After the steel truss girder of a cable-stayed bridge is erected, in order to reduce the out-of-plane bending moment of the crossbeams, the top longitudinal beam of the steel truss girder at the top of the auxiliary pier is sometimes disconnected and not connected temporarily. This measure helps to optimize the overall stress state of the bridge and reduce the bending stress of the crossbeams. However, after disconnecting the top longitudinal beam, the local stiffness of the bridge will decrease, especially at the disconnection point, where the load-bearing capacity will drop significantly. When the subsequent scaffolding machine is used to lay the entire bridge deck, it needs to step on the previous bridge deck panel to lay the next one. However, since the top longitudinal beam has been disconnected, if the scaffolding machine works directly on it, it may cause excessive stress on the disconnected steel truss girder, resulting in deformation or damage, posing a safety hazard. Summary of the Invention

[0003] This application provides a method for laying precast slabs for cantilever cable-stayed bridges and a cable-stayed bridge structure, which can solve the technical problem in the prior art where, in order to reduce the out-of-plane bending moment of the crossbeams, some longitudinal beams of the steel truss are broken, resulting in a reduction in the local stiffness of the bridge and posing a safety hazard to the subsequent laying of bridge deck panels.

[0004] In a first aspect, embodiments of this application provide a method for laying precast cantilever slabs for cable-stayed bridges, including:

[0005] Keep the top longitudinal beam above the target steel truss beam in a disconnected state, and set temporary supports below the separation point of the top longitudinal beam beam. Lay precast slabs on top of all steel truss beams.

[0006] The target steel truss girder and the precast slab above the adjacent steel truss girder are lifted, the lifting fulcrum located on the top of the auxiliary pier is raised to support the target steel truss girder, the top longitudinal beam above the target steel truss girder is connected, and the temporary support is removed.

[0007] Place the hoisted precast slabs back to their original positions, perform wet joints between all adjacent precast slabs, and replace the lifting support points with permanent supports.

[0008] The target steel truss is a steel truss located above the auxiliary pier.

[0009] In conjunction with the first aspect, in one embodiment, the top longitudinal beam above the target steel truss is kept in a disconnected state, and temporary supports are provided below the separation point of the top longitudinal beam. Precast slabs are then laid above all the steel trusses, specifically including:

[0010] Based on the load and span of the cable-stayed bridge, the location of the auxiliary piers was determined and the concrete was poured.

[0011] The steel truss is erected, and based on the position of the auxiliary pier, the steel truss above the auxiliary pier is marked as a target steel truss;

[0012] The steel truss is spliced, the top longitudinal beam above the target steel truss is kept in a disconnected state, and the spliced steel truss forms a cable-stayed bridge cantilever;

[0013] A temporary support is arranged below the separation of the top longitudinal beam, so that the gap between the end face of the top longitudinal beam of the target steel truss and the end face of the top longitudinal beam of the adjacent steel truss of the target steel truss is within a preset gap;

[0014] The precast slab is laid on all the steel trusses in sequence by a slab laying device;

[0015] The cable-stayed bridge cantilevers are two groups, and the two groups of cable-stayed bridge cantilevers are oppositely arranged along the transverse bridge direction.

[0016] In an embodiment, the temporary support arranged below the separation of the top longitudinal beam specifically includes:

[0017] A steel pipe pile with a length less than the height of the steel truss is placed below the separation of the top longitudinal beam, and the positions of the steel pipe piles in the two groups of cable-stayed bridge cantilevers are opposite;

[0018] The bottom of the steel pipe pile is connected to the bottom longitudinal beam of the target steel truss, and the rod body of the steel pipe pile is connected to the diagonal bracing beam of the target steel truss;

[0019] Based on the height difference between the target steel truss and the steel pipe pile, the thickness of the coping beam at the top of the steel pipe pile is determined, and the steel pipe piles at corresponding positions in the two groups of cable-stayed bridge cantilevers are connected by the coping beam in the transverse direction.

[0020] In an embodiment, the precast slab is laid on all the steel trusses in sequence by a slab laying device, specifically including:

[0021] The slab laying device moves to one end of the cable-stayed bridge cantilever to lay the first precast slab on the steel truss;

[0022] The slab laying device takes the laid first precast slab as a stepping plate to lay the next precast slab adjacent to the first precast slab, until all the steel trusses are paved.

[0023] In an embodiment, the hoisting of the target steel truss and the precast slab above the adjacent steel truss of the target steel truss, the lifting of the lifting support point at the top of the auxiliary pier to support the target steel truss, the connection of the top longitudinal beam above the target steel truss, and the removal of the temporary support specifically include:

[0024] The hoisting equipment hoists the target steel truss and the precast slab above the adjacent steel truss of the target steel truss, and places the hoisted precast slab in an adjacent segment, which is one precast slab adjacent to the hoisted precast slab;

[0025] Lifting the lifting fulcrum on the top of the auxiliary pier until the top of the lifting fulcrum abuts against the bottom of the target steel truss girder;

[0026] Connecting the top longitudinal beam above the target steel truss girder in a disconnected state by using the connecting piece, and removing the temporary support.

[0027] In an embodiment, the lifting fulcrum comprises a lifting oil cylinder and a supporting surface at the telescopic end of the lifting oil cylinder and towards the bottom of the target steel truss girder.

[0028] In an embodiment, the precast plate is placed in situ, wet joints are made between all adjacent precast plates, and the lifting fulcrum is replaced by a formal support, specifically comprising:

[0029] The target steel truss girder and the precast plate above the adjacent steel truss girder of the target steel truss girder are placed in situ by hoisting equipment, and then wet joint operations are performed between all adjacent precast plates;

[0030] Based on the hardness of the wet joint, the lifting fulcrum is lowered and removed, and a formal support is arranged at the original lifting fulcrum.

[0031] In a second aspect, the embodiments of the present application provide a cable-stayed bridge structure, which is obtained based on the above-mentioned cable-stayed bridge cantilever precast plate laying method, and the cable-stayed bridge structure comprises:

[0032] A pier bottom assembly, which comprises a plurality of auxiliary piers arranged at intervals, and the top of each auxiliary pier is provided with a support piece mounting area for mounting different support pieces according to the engineering progress;

[0033] A deck assembly above the pier bottom assembly, which comprises two groups of oppositely arranged cable-stayed bridge cantilevers, the cable-stayed bridge cantilevers comprise a plurality of steel trusses connected end to end, and the steel truss above the auxiliary pier is provided with a temporary support mounting area.

[0034] In combination with the second aspect, in an embodiment, the support piece mounting area comprises a lower groove arranged axially along the auxiliary pier, and the inner wall of the lower groove is provided with a support piece abutting frame.

[0035] In an embodiment, the pier bottom assembly further comprises a cable tower, and the cable tower is provided with a plurality of stay cables diverging along the bridge direction for connecting a steel truss respectively.

[0036] The technical solutions provided by the embodiments of the present application have the following beneficial effects:

[0037] By setting temporary support under the separation of the top longitudinal beam of the target steel truss beam, the stability of the cable-stayed bridge cantilever during the laying of the prefabricated plate is ensured, and safety accidents caused by unstable structure are effectively prevented. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to make the technical solutions in the embodiments of the present application clearer, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0039] Figure 1 A flow chart of a cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is provided.

[0040] Figure 2 A target steel truss beam position diagram in a cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is provided.

[0041] Figure 3 A temporary support position diagram in a cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is provided.

[0042] Figure 4 A side view of a temporary support structure in a cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is provided.

[0043] Figure 5 A cable-stayed bridge structure diagram provided by the present application is provided.

[0044] In the figure: 1, target steel truss beam; 2, temporary support; 201, steel pipe pile; 202, copy cushion beam; 3, auxiliary pier; 4, lifting support point; 5, cable tower; 501, cable. DETAILED DESCRIPTION

[0045] In order to make the technical solutions in the embodiments of the present application clearer, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0046] The embodiment of the present application provides a cable-stayed bridge cantilever prefabricated plate laying method and a cable-stayed bridge structure, which can solve the technical problem that the local stiffness of the bridge is reduced due to the disconnection of part of the steel truss girder longitudinal beam in the cable-stayed bridge cantilever of the prior art to reduce the out-of-plane bending moment of the cross beam, thereby causing a safety hazard to subsequent bridge deck plate laying work.

[0047] In a first aspect, the present application provides a cable-stayed bridge cantilever prefabricated plate laying method, Figure 1 A flow chart of the cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is shown in Figure 1 The cable-stayed bridge cantilever prefabricated plate laying method specifically comprises the following steps:

[0048] S1: keeping the top longitudinal beam above the target steel truss girder 1 in a disconnected state, arranging a temporary support 2 below the separation position of the top longitudinal beam, and laying prefabricated plates above all steel truss girders;

[0049] The plurality of steel truss girders are sequentially laid in the bridge longitudinal direction, and the plurality of steel truss girders are connected at the head and tail to form a cable-stayed bridge cantilever, Figure 2 A position diagram of the target steel truss girder 1 in the cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is shown in Figure 2 Among the plurality of steel truss girders, the steel truss girder above the auxiliary pier 3 is designated as the target steel truss girder 1, the top longitudinal beam of the target steel truss girder 1 and the top longitudinal beam of the steel truss girder adjacent to the target steel truss girder 1 are kept in a disconnected state during splicing to reduce the out-of-plane bending moment, and the number of steel truss girders adjacent to the target steel truss girder 1 is two, which are located on the two sides of the target steel truss girder 1. Therefore, the temporary supports 2 on the same target steel truss girder 1 are two groups, which are located on the two sides of the target steel truss girder 1. The top of the installed temporary support 2 abuts against the bottom of the separation position of the top longitudinal beam of the target steel truss girder 1 and the steel truss girder adjacent to the target steel truss girder 1. Then, the prefabricated plate laying work is carried out. Due to the support of the temporary support 2, the prefabricated plate above the target steel truss girder 1 has sufficient bearing capacity and can stably support the plate laying equipment to carry out the full-bridge prefabricated plate laying work.

[0050] S2: hoisting the prefabricated plate above the target steel truss girder 1 and the steel truss girder adjacent to the target steel truss girder 1, lifting the lifting support point 4 on the top of the auxiliary pier 3 to support the target steel truss girder 1, connecting the top longitudinal beam above the target steel truss girder 1, and removing the temporary support 2;

[0051] After the prefabricated slabs are all laid, the deck part of the cable-stayed bridge is formed, at this time, the support source of the target steel truss 1 needs to be transferred from the temporary support 2 to the auxiliary pier 3 while keeping the current posture of the target steel truss 1, in order to reduce the vertical load of the target steel truss 1 and the risk of structural stress during the support source transfer process, the target steel truss 1 and the prefabricated slabs above the adjacent steel trusses of the target steel truss 1 are first lifted, then the lifting support point 4 at the top of the auxiliary pier 3 is raised to keep the current splicing posture of the target steel truss 1 and the adjacent steel trusses of the target steel truss 1, and the connection between the top longitudinal beams of the target steel truss 1 and the adjacent steel trusses of the target steel truss 1 is performed, finally the temporary support 2 is removed, at this time, the target steel truss 1 is supported by the auxiliary pier 3, and the support source transfer process is completed.

[0052] S3: Place the lifted prefabricated slab to the original position, perform wet connection between all adjacent prefabricated slabs, and replace the lifting support point 4 with the formal support.

[0053] The connection between the target steel truss 1 and the adjacent steel trusses of the target steel truss 1 is completed, the bottom of the target steel truss 1 is supported by the auxiliary pier 3, the structure of the cable-stayed bridge is formed, the lifted prefabricated slab is placed to the original position, and the full-bridge wet connection work is performed, and the cable-stayed bridge cantilever prefabricated slab laying is completed.

[0054] Further, step S1 specifically includes:

[0055] S101: Determine the position of the auxiliary pier 3 based on the load and span of the cable-stayed bridge, and pour the auxiliary pier 3;

[0056] Firstly, the position of the auxiliary pier 3 on the axis of the cable-stayed bridge needs to be determined, the selected position of the auxiliary pier 3 is generally determined based on the span, deck load and foundation of the cable-stayed bridge and other factors, in a possible embodiment of the present application, the auxiliary pier 3 is arranged in the area close to the end of the cable-stayed bridge, for a large-span cable-stayed bridge, especially in the end area, due to the cantilever effect, the end of the cable-stayed bridge may be subjected to large bending moment and shear force, arranging the auxiliary pier 3 in this area can effectively disperse these forces and enhance the overall stability of the cable-stayed bridge, at the same time, arranging the auxiliary pier 3 in the end of the cable-stayed bridge can also bring certain convenience to the construction, which can reduce the material consumption and construction cost.

[0057] S102: Erect the steel truss, and mark the steel truss above the auxiliary pier 3 as the target steel truss 1 based on the position of the auxiliary pier 3;

[0058] Based on the design drawings of the cable-stayed bridge, the steel trusses are erected in sequence, so that the erected steel trusses are all within the design posture allowable deviation range of the design drawings, and then the steel truss above the auxiliary pier 3 is marked as the target steel truss 1.

[0059] S103: splice the steel truss, keep the top longitudinal beam above the target steel truss 1 in a disconnected state, and the spliced steel truss forms a cable-stayed bridge cantilever;

[0060] The commonly used steel truss generally includes parallel top longitudinal beams, bottom longitudinal beams, and diagonal bracing beams between the top longitudinal beams and the bottom longitudinal beams. The two ends of the top longitudinal beam of the target steel truss 1 are separated from the top longitudinal beams of the adjacent steel trusses on both sides, the remaining steel trusses are all spliced, forming a cable-stayed bridge cantilever, and the cable-stayed bridge cantilever is in two groups, and the two groups of cable-stayed bridge cantilevers are oppositely arranged along the transverse bridge direction.

[0061] S104: A temporary support 2 is arranged below the separation of the top longitudinal beam, so that the gap between the end face of the top longitudinal beam of the target steel truss 1 and the end face of the top longitudinal beam of the adjacent steel truss of the target steel truss 1 is within the preset gap;

[0062] Figure 3 A schematic view of the position of the temporary support 2 in the cable-stayed bridge cantilever prefabricated plate laying method provided by the present application is shown in FIG. 2. Figure 3 As shown in FIG. 2, the top of the temporary support 2 supports the top separation of the target steel truss 1 and the adjacent steel truss of the target steel truss 1. In step S102, all the steel trusses have been laid according to the design drawing, and the target steel truss 1 is in the correct position. Therefore, the temporary support 2 can maintain the current splicing position of the target steel truss 1 and the adjacent steel truss of the target steel truss 1, and support them to prevent the target steel truss 1 from being stressed and displaced during the prefabricated plate presetting process.

[0063] S105: The prefabricated plate is laid on all the steel trusses in sequence by the laying equipment;

[0064] The arrangement of the temporary support 2 gives the target steel truss 1 sufficient bearing capacity to bear the laying equipment, facilitating the prefabricated plate laying work on the entire bridge deck.

[0065] Further, the arrangement of the temporary support 2 in step S104 specifically includes:

[0066] S1041: Place a steel pipe pile 201 with a length less than the height of the steel truss below the separation of the top longitudinal beam, and the steel pipe piles 201 in the two groups of cable-stayed bridge cantilevers are oppositely arranged;

[0067] S1042: Connect the bottom of the steel pipe pile 201 to the bottom longitudinal beam of the target steel truss 1, and connect the rod body of the steel pipe pile 201 to the diagonal bracing beam of the target steel truss 1;

[0068] S1043: Determine the thickness of the coping beam 202 on the top of the steel pipe pile 201 based on the height difference between the target steel truss 1 and the steel pipe pile 201, and connect the steel pipe piles 201 at the corresponding positions in the two groups of cable-stayed bridge cantilevers by the coping beam 202 in the transverse direction.

[0069] Figure 4 A side view of a temporary support structure in a cable-stayed bridge cantilever precast slab laying method provided in the present application is shown in Figure 4 As shown in the drawings, the length of the steel pipe pile 201 is less than the height of the steel truss beam, when the steel pipe pile 201 is connected to the target steel truss beam 1, the top of the steel pipe pile 201 is spaced a certain distance from the bottom surface of the top longitudinal beam of the target steel truss beam 1, the thickness of the coping beam 202 is equal to the spacing distance, so that the coping beam 202 is embedded between the top of the steel pipe pile 201 and the bottom surface of the top longitudinal beam of the target steel truss beam 1. The coping beam 202 has a certain length, and the length is not less than the spacing distance between the two groups of cable-stayed bridge cantilevers, so that the two ends of the coping beam 202 are connected to the top of the steel pipe pile 201 at the corresponding positions of the two groups of cable-stayed bridge cantilevers at the same time.

[0070] Further, in step S105, the precast slab laying is sequentially performed on all steel truss beams by the slab laying equipment, specifically including:

[0071] S1051: The slab laying equipment moves to one end of the cable-stayed bridge cantilever to lay the first precast slab on the steel truss beam;

[0072] S1052: The slab laying equipment lays the next precast slab adjacent to the first precast slab using the first precast slab as a stepping plate, until all steel truss beams are paved.

[0073] The precast slab laying starts from one end of the cable-stayed bridge cantilever, the laying equipment lays the second precast slab adjacent to the first precast slab using the first precast slab as a stepping plate, then lays the third precast slab using the second precast slab as a stepping plate, and so on, until all steel truss beams are paved.

[0074] Further, step S2 specifically includes:

[0075] S201: The hoisting equipment hoists the target steel truss beam 1 and the precast slab above the adjacent steel truss beam of the target steel truss beam 1, and places the hoisted precast slab in the adjacent segment, which is one precast slab adjacent to the hoisted precast slab;

[0076] S202: The lifting support point 4 located at the top of the auxiliary pier 3 is raised until the top of the lifting support point 4 abuts against the bottom of the target steel truss beam 1;

[0077] S203: The top longitudinal beam above the target steel truss beam 1 in the disconnected state is connected by using a connecting piece, and the temporary support 2 is removed.

[0078] A prefabricated slab is a bay, and the length of the prefabricated slab in the bridge direction is greater than the length of the steel truss girder in the bridge direction. Therefore, a prefabricated slab will cover the target steel truss girder 1 and the steel truss girder adjacent to the target steel truss girder 1 at the same time. After lifting the prefabricated slab, it is temporarily placed on the adjacent bay. Then, the lifting support point 4 on the top of the auxiliary pier 3 is raised to maintain the current splicing posture of the target steel truss girder 1 and the steel truss girder adjacent to the target steel truss girder 1, so as to facilitate the connection work between the top longitudinal beam of the target steel truss girder 1 and the top longitudinal beam of the steel truss girder adjacent to the target steel truss girder 1. When the connection work between the top longitudinal beam of the target steel truss girder 1 and the top longitudinal beam of the steel truss girder adjacent to the target steel truss girder 1 is completed, it means that the cantilever of the cable-stayed bridge has been completely spliced, and the support source of the target steel truss girder 1 has also been completely transferred. The construction personnel remove the temporary support 2.

[0079] Among them, the lifting support point 4 includes a lifting oil cylinder and a support surface located at the telescopic end of the lifting oil cylinder and facing the bottom of the target steel truss girder 1.

[0080] Further, S3 specifically includes:

[0081] S301: Place the prefabricated slab being lifted above the target steel truss girder 1 and the steel truss girder adjacent to the target steel truss girder 1 in place by the lifting equipment, and then perform wet joint operation between all adjacent prefabricated slabs;

[0082] S302: Based on the hardness of the wet joint, the lifting support point 4 is lowered and removed, and a formal support is arranged at the original lifting support point 4.

[0083] After the prefabricated slab being lifted is placed in place, the splicing joint between the adjacent prefabricated slabs is wet jointed. During this period, the lifting support point 4 is continuously maintained in the lifting state. After the hardness of the splicing joint meets the requirements, the lifting support point 4 is lowered and replaced with a formal support. Thus, the cantilever prefabricated slab laying of the cable-stayed bridge is completely finished.

[0084] In a second aspect, the embodiments of the present application also provide a cable-stayed bridge structure, which is laid based on the above-mentioned cantilever prefabricated slab laying method of the cable-stayed bridge, Figure 5 A structural diagram of a cable-stayed bridge structure provided by the present application is shown in Figure 5 As shown, the cable-stayed bridge structure includes a pier bottom assembly and a deck assembly located above the pier bottom assembly. The pier bottom assembly includes a plurality of auxiliary piers 3 arranged at intervals, and the top of each auxiliary pier 3 is provided with a support mounting area for replacing different supports according to the engineering progress. The deck assembly includes two groups of oppositely arranged cable-stayed bridge cantilevers. Each cable-stayed bridge cantilever includes a plurality of steel trusses connected end to end, and a temporary support mounting area is arranged on the steel truss above the auxiliary pier 3.

[0085] In one possible implementation, the support member mounting area is a lower groove arranged along the auxiliary pier 3, and the lower groove is provided with a support member abutting frame, so that different types of support members can be embedded in the lower groove and fixed via the support member abutting frame in different construction stages.

[0086] The steel truss generally comprises top longitudinal beams, bottom longitudinal beams arranged in parallel, and diagonal bracing beams between the top longitudinal beams and the bottom longitudinal beams. The temporary support mounting area is located on the bottom longitudinal beams and the diagonal bracing beams of the steel truss, and the temporary support mounting areas of the steel trusses in the two groups of cable-stayed bridge cantilevers are opposite to each other. The external temporary support 2 is connected with the steel truss via the temporary support mounting area.

[0087] Further, the pier bottom assembly further comprises a cable tower 5, and the cable tower 5 is provided with a plurality of stay cables 501 arranged along the bridge direction and used for connecting a steel truss, respectively. The cable tower 5 extends out of the top of the cable-stayed bridge cantilever, and the plurality of stay cables 501 are oppositely arranged on both sides of the bridge direction of the cable tower 5, and the stay cables 501 on the same side are arranged along the length direction of the cable tower 5. The free ends of the plurality of stay cables 501 are connected with a steel truss, respectively.

[0088] In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise expressly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through an intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0089] It should be noted that in the present application, relational terms such as "first" and "second", and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0090] The foregoing detailed description of the application has been presented for purposes of illustration and description. Various modifications and changes can be made to these embodiments without departing from the spirit and scope of the application. It is intended that the scope of the application should not be limited by the particular representative embodiments described above.

Claims

1. A method for laying precast cantilever slabs in a cable-stayed bridge, characterized in that, include: Keep the top longitudinal beam above the target steel truss (1) in a disconnected state, and set up temporary support (2) below the separation point of the top longitudinal beam, and lay precast slabs on top of all steel trusses; Lift the target steel truss (1) and the precast slab above the adjacent steel truss of the target steel truss (1), lift the lifting support (4) located on the top of the auxiliary pier (3) to support the target steel truss (1), connect the top longitudinal beam above the target steel truss (1), and remove the temporary support (2). Place the lifted precast slab back to its original position, perform wet jointing between all adjacent precast slabs, and replace the lifting support (4) with the formal support; The target steel truss (1) is a steel truss located above the auxiliary pier (3).

2. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 1, characterized in that, The top longitudinal beam above the target steel truss (1) is kept in a disconnected state, and temporary supports (2) are set below the separation point of the top longitudinal beam. Precast slabs are laid on top of all steel trusses, specifically including: Based on the load and span of the cable-stayed bridge, the location of the auxiliary pier (3) was determined and poured. Erect steel truss beams, and based on the position of the auxiliary pier (3), mark the steel truss beam located above the auxiliary pier (3) as the target steel truss beam (1); Splice the steel truss girder, and keep the top longitudinal beam above the target steel truss girder (1) in a broken state, and the spliced ​​steel truss girder forms a cable-stayed bridge cantilever; Temporary support (2) is set below the separation point of the top longitudinal beam so that the gap between the end face of the top longitudinal beam of the target steel truss beam (1) and the end face of the top longitudinal beam of the adjacent steel truss beam of the target steel truss beam (1) is within the preset gap; Precast slabs are laid sequentially over all steel trusses using a slab laying equipment. The cable-stayed bridge has two sets of cantilever arms, and the two sets of cantilever arms are arranged opposite each other along the transverse direction of the bridge.

3. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 2, characterized in that, The provision of temporary support (2) below the separation point of the top longitudinal beam specifically includes: Steel pipe piles (201) with a length less than the height of the steel truss girder are placed below the separation point of the top longitudinal beam, and the steel pipe piles (201) in the two sets of cable-stayed bridge cantilever are positioned opposite each other. The bottom of the steel pipe pile (201) is connected to the bottom longitudinal beam of the target steel truss beam (1), and the rod of the steel pipe pile (201) is connected to the diagonal bracing beam of the target steel truss beam (1). Based on the height difference between the target steel truss (1) and the steel pipe pile (201), the thickness of the pad beam (202) located at the top of the steel pipe pile (201) is determined, and the pad beam (202) is used to laterally connect the steel pipe piles (201) at corresponding positions in the two sets of cable-stayed bridge cantilever.

4. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 2, characterized in that, The process of sequentially laying precast slabs over all steel truss beams using a slab-laying device specifically includes: The slab laying equipment moves to one end of the cantilever of the cable-stayed bridge to lay the first precast slab on the steel truss. The slab laying equipment uses the first precast slab that has been laid as a step to lay the next precast slab adjacent to the first precast slab, until all steel truss beams are covered.

5. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 1, characterized in that, The lifting of the target steel truss girder (1) and the precast slab above the adjacent steel truss girder (1), raising the lifting support point (4) located on the top of the auxiliary pier (3) to support the target steel truss girder (1), connecting the top longitudinal beam above the target steel truss girder (1), and removing the temporary support (2) specifically includes: The hoisting equipment lifts the target steel truss (1) and the precast slab above the adjacent steel truss (1), and places the lifted precast slab in the adjacent section, wherein the adjacent section is one of the precast slabs adjacent to the lifted precast slab; Raise the lifting fulcrum (4) located on the top of the auxiliary pier (3) until the top of the lifting fulcrum (4) abuts against the bottom of the target steel truss beam (1); Connect the top longitudinal beam above the target steel truss (1) which is in a disconnected state using connectors, and remove the temporary support (2).

6. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 5, characterized in that, The lifting fulcrum (4) includes a lifting cylinder and a support surface located at the telescopic end of the lifting cylinder and facing the bottom of the target steel truss (1).

7. The method for laying precast cantilever slabs for cable-stayed bridges as described in claim 1, characterized in that, The process of placing the lifted precast slabs back to their original positions, wet-jointing all adjacent precast slabs, and replacing the lifting support (4) with a permanent support includes: The target steel truss (1) and the precast slabs that were lifted above the target steel truss (1) were placed back to their original positions using hoisting equipment, and then wet jointing was performed between all adjacent precast slabs. Based on the hardness of the wet joint, the lifting support (4) is lowered and removed, and a formal support is installed at the original lifting support (4).

8. A cable-stayed bridge structure, laid according to the cantilever precast slab laying method for cable-stayed bridges as described in any one of claims 1 to 7, characterized in that, The cable-stayed bridge structure includes: The pier base assembly includes several spaced auxiliary piers (3), and the top of each auxiliary pier (3) is provided with a support installation area for installing different supports according to the progress of the project. The bridge deck assembly located above the pier base assembly includes two sets of oppositely arranged cable-stayed bridge cantilever arms, each cable-stayed bridge cantilever arm including multiple steel trusses connected end to end, and a temporary support installation area is provided on the steel truss above the auxiliary pier (3).

9. A cable-stayed bridge structure as described in claim 8, characterized in that, The support installation area includes a lower groove arranged along the axial direction of the auxiliary pier (3), and a support support frame is provided on the inner wall of the lower groove.

10. A cable-stayed bridge structure as described in claim 9, characterized in that, The pier base assembly also includes a cable tower (5), which has several cables that radiate along the bridge direction for connecting to a steel truss cable (501) respectively.

Images