CN115961549A - Rear-feeding beam type erection construction method for large-tonnage whole-section steel beam of cable-stayed bridge - Google Patents

Abstract

The present application discloses a construction method of post-feeding girder type erection of large-tonnage steel girders of a cable-stayed bridge. By building a longitudinal support next to the main tower pier, a transverse support is built on one side of the longitudinal support, and then the main structure is completed on the longitudinal support. The construction of the steel-concrete joint section on both sides of the tower; and use the lifting station to lift the welding modules to the horizontal support one by one, and assemble them into standard sections, complete the assembly and transfer of several standard sections, and then place the steel on the longitudinal support. The mixed joint section and multiple standard sections are assembled and welded into a whole, and the horizontal support is raised until it is flush with the surface of the starting end; then the standard section assembly is completed under the gantry crane, and the standard section is moved longitudinally to the bridge erection by using the lifting station and the gantry crane Below the machine, the splicing of the standard section and the steel-concrete joint section is finally completed to complete the erection of the steel beam. In order to complete the steel box girder splicing steps in areas with narrow construction sites and complex surrounding terrain.

Description

A construction method of rear-fed girder type erection of large-tonnage whole-segment steel girders of cable-stayed bridges

technical field

The present application relates to the field of construction of cable-stayed bridges, in particular to a method for constructing large-tonnage full-segment steel girders of a cable-stayed bridge with post-feeding girder type erection.

Background technique

At present, there are generally three methods for erecting steel girders of cable-stayed bridges. One is the cantilever assembly method. The main feature of this method is to transport the girder sections to the bridge position to be erected, and then use the deck crane to vertically lift and erect them in place. This method can only be realized when there is a transportation channel at the bridge site; one is the longitudinal push method, the main feature of this method is to assemble a row of temporary piers at the bridge site, erect at one end and push it into place, then hang the cable To realize the conversion of the cable-stayed bridge system, this method needs to have an assembly site and a transportation channel at one or both ends of the bridge. One is the full hall support method, that is, compared with the concrete cast-in-place beam support, the full hall support is erected along the main beam and installed on the support. The steel box girder manufactures the tire frame. The steel box girder plate is transported to the site after being unloaded in the factory. The steel beam is assembled and welded on the tire frame by an on-site crane. Finally, the stay cable is hung, and the system conversion is completed by tensioning the steel box. The beam is detached from the tire frame to complete the erection of the steel box girder, so as to avoid the subsidence of the bracket and affect the assembly accuracy of the steel box girder. The amount of steel required for the bracket is quite large and the requirements for the foundation treatment of the bracket are very high.

However, when building steel girder cable-stayed bridges in places with limited construction sites such as crossing existing roads, bridges, mountains, and rivers, especially on expressways that have already been in operation, not only will the construction site be narrow and the terrain complex, but the construction It is also easy to interfere with the ground traffic, and it is difficult to complete the steel box girder segmental assembly construction through the cantilever assembly method and the longitudinal push method, so there is still room for improvement.

Contents of the invention

In order to complete the splicing steps of steel box girders in areas with narrow construction sites and complex surrounding terrains, the present application provides a construction method for rear-feeding girder erection of large-tonnage full-segment steel girders of cable-stayed bridges.

The construction method of rear-feeding girder type erection of a large tonnage entire section steel girder of a cable-stayed bridge provided by the application adopts the following technical scheme:

A cable-stayed bridge large-tonnage full-segment steel girder post-feeding construction method comprises the following steps:

S1: Construction preparation: divide the standard section of the steel box girder into three combined modules for fabrication, and pre-assemble in the pre-assembly field;

S2: Bracket erection: build a longitudinal bracket next to the main tower pier, the longitudinal bracket extends along the bridge direction, and the supporting surface of the longitudinal bracket is located above the road, and a horizontal bracket is built on the side of the longitudinal bracket, the supporting surface of the horizontal bracket and the support of the longitudinal bracket face connection;

S3: Construction of the steel-concrete joint section: complete the construction of the steel-concrete joint section on both sides of the main tower on the longitudinal support;

S4: Lifting station construction: build a lifting station at the horizontal support, and the lifting station is used to lift the combined module to the horizontal support;

S5: Construction of the initial section: use the lifting station to lift the assembly and welding modules to the horizontal support one by one, and assemble and weld them into a steel box girder standard section, and move the standard section horizontally to the support surface of the longitudinal support, and then move vertically to the vertical At the end of the bracket away from the main tower, complete the assembly and transfer of several standard sections according to the above steps, and then assemble and weld the steel-concrete joint section and multiple standard sections on the longitudinal support to complete the side of the main tower The initial section of construction;

S6: Lifting of the horizontal support: raise the support surface of the horizontal support to be flush with the upper surface of the initial section and connect;

S7: Install gantry crane and bridge erecting machine: Install gantry crane and bridge erecting machine on the upper surface of the initial section, and the gantry crane and bridge erecting machine can move along the bridge direction;

S8: Post-feeding beam construction: use the lifting station to lift the assembly and welding modules one by one to the support surface of the transverse support, and assemble and weld them into a steel box girder standard section, and then move the three assembly and welding modules to the initial section The surface and vertically move to the bottom of the gantry crane, and adjust the position of the three combined modules through the gantry crane, then assemble the three combined modules into a standard segment, and then move the standard segment longitudinally to the bottom of the bridge erecting machine, and the bridge erecting machine lifts the beam and vertically After the standard segment is moved longitudinally in place, it is rotated 90 degrees. Then drop the beam, and finally complete the splicing of the standard section and the steel-concrete joint section to complete the erection of the first steel beam;

S9: Repeat the above S8, the bridge erecting machine continues to move forward, and completes the assembly of the remaining steel box girder standard sections.

By adopting the above technical scheme, the standard section of the steel box girder is divided into three welding modules, the purpose is to facilitate the transfer of the steel box girder in a narrow area, reduce the lifting weight of the section and facilitate the lateral movement on the horizontal support. In addition, the steel box girder is lifted, moved horizontally, and moved vertically from the side of the main tower to facilitate the construction of the initial section of the steel box girder, and then the horizontal support is lifted to transfer the beam section to the surface of the initial section. The standard section is placed under the bridge erecting machine, rotated 90 degrees and then erected. This solution solves the problem that the suspension method cannot meet the transportation conditions and there is no place under the bridge to hoist the entire steel box girder. Faced with the problem that the amount of steel required for the support is quite large and the treatment of the support foundation is very demanding, and while improving the construction efficiency of the steel box girder, it reduces the interference of the railway bridge on residents, urban ground traffic and expressway viaducts. During the erection of the box girder, the impact on the expressway and the Wuhan-Guangzhou high-speed railway will be minimized, and the purpose of completing the splicing steps of the steel box girder in the narrow construction site and complex surrounding terrain will be achieved.

Preferably, in said S5, a transverse guide rail is installed on the transverse support, the transverse guide rail extends laterally to the longitudinal support, and a longitudinal guide rail is installed on the longitudinal support, the longitudinal guide rail is connected with the transverse guide rail, and the longitudinal guide rail extends along the bridge direction, During standard segmental movement, first move laterally along the transverse guide rails to the longitudinal support, and then longitudinally move along the longitudinal guide rails to the end of the longitudinal support.

By adopting the above technical scheme, the horizontal and vertical guide rails are designed so that the standard segments can be positioned accurately, which is conducive to the assembly of the standard segments.

Preferably, the lifting station includes two rows of supporting frames distributed horizontally, the horizontal frame is located between the two rows of supporting frames, and both sides of the horizontal frame are respectively vertically slidably connected to the inner sides of the two rows of supporting frames.

By adopting the above technical solution, the support frame not only supports the lifting station, but also limits and guides the transverse support, which is conducive to the stable lifting of the transverse support and improves the transfer efficiency of the steel box girder.

Preferably, said lifting station is provided with lifting means for lifting the transverse support.

By adopting the above-mentioned technical scheme, the automatic lifting of the horizontal support can be realized, the investment in crane equipment can be reduced, and the installation efficiency of the horizontal support can be improved at the same time.

Preferably, in the above S6, after the support surface of the transverse support is raised to the designed height, the column below the transverse support is extended upwards, and the column supports the support surface of the transverse support.

By adopting the above technical solution, it is beneficial to improve the stability of the transverse support.

Preferably, in said S8, a mobile protective shed is built at the expressway, and the mobile protective shed moves along the direction of the expressway. During the installation process of the standard segment, the mobile protective shed moves below the standard segment.

By adopting the above technical scheme, the mobile protective shed plays a protective role, which is beneficial to improving construction safety.

Preferably, said S3 includes:

S3.1: Install the tire frame on the longitudinal support, then assemble the steel box girder on the tire frame, remove the tire frame after the tailor welding of the steel box girder, and use the distribution beam to support the steel box girder on the longitudinal support;

S3.2: Binding steel bars and pouring concrete for the bottom slab of the steel-concrete joint section;

S3.3: After the bottom slab concrete reaches the design strength, install the opposite tension structure on the top surface of the steel box girder, and apply pre-tension force to each opposite tension steel bar, so that the steel-concrete joint section and the lower beam of the main tower are consolidated;

S3.4: Establish the inner form in the steel-concrete joint section, and pour the web and roof concrete.

By adopting the above technical scheme, it is beneficial to improve the construction accuracy and stability of the steel-concrete combination section.

Description of drawings

Fig. 1 is a schematic diagram of the status of assembly and welding modules assembled into standard sections on transverse supports in a construction method of post-feeding beam type erection of large-tonnage full-segment steel girders of a cable-stayed bridge according to an embodiment of the present application.

FIG. 2 is an enlarged schematic view of point A in FIG. 1 .

Fig. 3 is a schematic diagram of the assembled state of the initial section in the erection method of a large-tonnage full-segment steel girder of a cable-stayed bridge according to an embodiment of the present application.

Fig. 4 is a schematic diagram of the state when the gantry crane and the suspension bridge crane are installed in the construction method of the large-tonnage full-segment steel girder of the cable-stayed bridge according to the embodiment of the present application.

Fig. 5 is a schematic diagram of the state of the standard section of the cantilevered steel box girder in the construction method of the post-feeding girder type erection method of the large-tonnage whole-segment steel girder of the cable-stayed bridge according to the embodiment of the present application.

Explanation of reference signs: 1. main tower; 2. steel-concrete combined section; 3. longitudinal support; 4. road; 5. lifting station; 51. support frame; 52. lifting device; 6. horizontal support; 7. standard section Section; 71. Welding module; 8. Transverse guide rail; 9. Longitudinal guide rail; 10. Initial section; 11. Upright column; 12. Bridge erecting machine; 13. Gantry crane;

Detailed ways

The present application will be described in further detail below in conjunction with accompanying drawings 1-5.

The embodiment of the present application discloses a method for constructing a cable-stayed bridge with a large tonnage full-segment steel girder rear-fed girder type erection. Include the following steps:

S1: Construction preparation: Referring to Figure 1 and Figure 2, the standard segment 7 of the steel box girder is divided into three combined modules for fabrication, and pre-assembled in the pre-assembled field;

S2: Bracket erection: Build a longitudinal support 3 next to the pier of the main tower 1, the longitudinal support 3 extends along the bridge direction, and the support surface of the longitudinal support 3 is located above the road 4, and build a horizontal support 6 on the side of the longitudinal support 3, and the horizontal support 6 The support surface of the support surface is connected with the support surface of the longitudinal support 3.

Wherein, the longitudinal support 3 and the transverse support 6 are all formed by erecting a distribution beam on the steel pipe column 11 of φ800mm and φ630mm, and installing a Bailey frame on the distribution beam, and the square distribution beam and the Bailey beam form the supporting surface of the support together. A stable support system is jointly formed by utilizing the horizontal connection system between the steel pipe columns 11. The steel pipe column 11 and its column cap are manufactured in the steel structure processing site, and are installed by two tower cranes installed at the position of the main tower 1. After adjusting the verticality of the column 11, the bottom is welded with the foundation embedded parts and stiffeners. The connection system and the hoop are installed when the steel pipe column 11 is installed to form a stable structure.

S3: Construction of steel-concrete joint section 2: Complete the construction of steel-concrete joint section 2 on both sides of the main tower 1 on the longitudinal support 3. The specific construction steps of steel-concrete joint section 2 are as follows:

S3.1: Install the tire frame on the longitudinal support 3, then assemble the steel box girder on the tire frame, remove the tire frame after the tailor welding of the steel box girder, and support the steel box girder on the longitudinal support 3 with distribution beams;

S3.2: Binding steel bars and pouring concrete for the bottom slab of steel-concrete joint section 2;

S3.3: After the bottom slab concrete reaches the design strength, install the anti-tension structure on the top surface of the steel box girder, and apply pre-tension force to each anti-tension steel bar, so that the steel-concrete joint section 2 and the lower beam of the main tower 1 are consolidated;

S3.4: Set up the inner formwork in the steel-concrete joint section 2, and pour the web and roof concrete.

Among them, in order to reduce the load-bearing and deformation of the steel-concrete joint section 2, the concrete is poured twice. The slab and roof are poured, and the pouring volume is 127.7m³. Before the first pouring, the supporting points are pre-lifted, and the pre-lifting value is determined according to the pre-compacted actual measurement data. At the same time, the steel box girder floor and partitions are stiffened at the supporting points. Before the second pouring, it is carried out after the roof with holes has been installed. The top plate of the steel box girder and the embedded parts at the top of the lower beam are connected through channel steel to form temporary anchorage, so as to reduce the load on the first concrete, reduce the deformation of the bracket, and prevent the first concrete and the lower beam from being separated during pouring. The contact surface produces excessive tensile stress and cracks.

S4: Construction of the lifting station 5: the lifting station 5 is built at the horizontal support 6, and the lifting station 5 is used to lift the combined module onto the horizontal support 6. The main structure of the lifting station 5 is a frame structure composed of steel pipes, which includes two columns of support frames 51, which are used as support parts. In addition, the main girder and the lifting beam are all made of Bailey beams. The hoisting equipment mainly includes two 8t winches and two 80t cranes. The hoists use Φ25mm steel wire ropes, five pulleys, and ten wire ropes. The lifting station 5 is located at the corner of the outer main tower 1 column near Dali, and is arranged parallel to the main beam of the support.

Wherein, the transverse support 6 is located between the two columns of support frames 51, and both sides of the support surface of the transverse support 6 are vertically slidably connected to the inner sides of the two columns of support frames 51. The support frames 51 not only support the lifting station 5, but also Simultaneously, it acts as a limit and a guide to the transverse support 6, which is beneficial to the stable lifting of the transverse support 6. A hoisting device 52 for driving the transverse support 6 up and down is installed on the main beam, and the hoisting device 52 is specifically a winch.

S5: Construction of the initial section 10: Referring to Fig. 2 and Fig. 3, the purpose of the construction of the initial section 10 is to provide a platform for assembling the gantry crane 13 and erecting bridges.

Use the lifting station 5 to lift the assembly and welding modules 71 to the transverse support 6 one by one, and assemble and weld them into the standard section 7 of the steel box girder, and move the standard section 7 laterally to the support surface of the longitudinal support 3, and then move vertically to the longitudinal support 3. At one end away from the main tower 1, complete the assembly and transfer of several standard segments 7 according to the above steps, and then assemble and weld the steel-concrete combination segment 2 and multiple standard segments 7 on the longitudinal support 3 to form a whole. The construction of the initial section 10 on one side of the main tower 1 is completed.

S6: Lifting of the transverse support 6: raising the support surface of the transverse support 6 to be flush with the upper surface of the starting section 10 and connecting;

S7: Install the gantry crane 13 and the bridge erecting machine 12: Referring to Fig. 4, install the gantry crane 13 and the bridge erecting machine 12 on the upper surface of the starting section 10, and the gantry crane 13 and the bridge erecting machine 12 can move along the bridge direction.

S8: Rear feeding beam construction: Referring to Figure 4 and Figure 5, use the lifting station 5 to lift the assembly and welding modules 71 to the support surface of the transverse support 6 one by one, and assemble and weld them into a steel box girder standard section 7, and then three The block assembly welding module 71 moves laterally to the upper surface of the initial section 10 and vertically moves to the bottom of the gantry crane 13, and adjusts the positions of the three combined modules through the gantry crane 13, then assembles the three combined modules into a standard segment 7, and then the standard The segment 7 moves longitudinally to below the bridge erecting machine 12 .

A mobile protective shed 14 is built at the expressway 4, and the mobile protective shed 14 moves along the direction of the expressway 4. During the installation process of the standard segment 7, the mobile protective shed 14 moves below the standard segment 7.

The bridge erecting machine 12 lifts the beam and moves vertically, and after the standard segment 7 is vertically moved in place, it rotates 90 degrees. Then drop the beam, and finally complete the splicing of the standard section 7 and the steel-concrete combination section 2 to complete the erection of the first steel beam.

S9: repeating the above S8, the bridge erecting machine 12 continues to move forward, and completes the assembly of the remaining steel box girder standard sections 7 .

All of the above are preferred embodiments of the application, and are not intended to limit the protection scope of the application. Therefore, all equivalent changes made according to the structure, shape, and principle of the application should be covered by the protection scope of the application. Inside.

Claims (7)

1. A post-feeding beam type erection construction method for large-tonnage whole-section steel beams of cable-stayed bridges is characterized by comprising the following steps of: the method comprises the following steps:

s1: construction preparation: dividing a standard segment (7) of the steel box girder into three combined modules for manufacturing, and performing pre-splicing on a pre-splicing field;

s2: erecting a support: building a longitudinal support (3) beside a pier of a main tower (1), wherein the longitudinal support (3) extends along a bridge direction, a supporting surface of the longitudinal support (3) is positioned above a road (4), a transverse support (6) is built on one side of the longitudinal support (3), and the supporting surface of the transverse support (6) is connected with the supporting surface of the longitudinal support (3);

s3: constructing the steel-concrete combined section (2): finishing the construction of the steel-concrete combined sections (2) at two sides of the main tower (1) on the longitudinal support (3);

s4: construction of a lifting station (5): a lifting station (5) is built at the position of the transverse support (6), and the lifting station (5) is used for lifting the combined module to the transverse support (6);

s5: constructing an initial section (10): lifting the assembly welding modules (71) to a transverse support (6) one by utilizing a lifting station (5), assembling and welding the assembly welding modules to form a standard steel box girder segment (7), transversely moving the standard segment (7) to a supporting surface of a longitudinal support (3), longitudinally moving the standard segment to one end position of the longitudinal support (3) far away from a main tower (1), assembling and transferring a plurality of standard segments (7) according to the steps, and assembling and welding a steel-concrete combination section (2) and a plurality of standard segments (7) on the longitudinal support (3) into a whole to complete construction of an initial section (10) on one side of the main tower (1);

s6: lifting the transverse bracket (6): lifting the supporting surface of the transverse bracket (6) to be flush with the upper surface of the initial section (10) and connecting;

s7: installing a gantry crane (13) and a bridge girder erection machine (12): a gantry crane (13) and a bridge girder erection machine (12) are arranged on the upper surface of the initial section (10), and the gantry crane (13) and the bridge girder erection machine (12) can move along the bridge direction;

s8: and (3) post-beam feeding construction: lifting the assembly welding modules (71) to the supporting surface of the transverse support (6) one by utilizing a lifting station (5), assembling and welding the assembly welding modules to form a standard steel box girder segment (7), transversely moving three assembly welding modules (71) to the upper surface of the initial section (10) and longitudinally moving the three assembly welding modules to the position below a gantry crane (13), adjusting the positions of the three assembly welding modules through the gantry crane (13), assembling the three assembly welding modules to form the standard segment (7), longitudinally moving the standard segment (7) to the position below a bridge girder erection machine (12), lifting and longitudinally moving the bridge girder erection machine (12), and rotating the standard segment (7) by ninety degrees after longitudinally moving the standard segment to the position. Then, the beam is dropped, and finally, the splicing of the standard section (7) and the steel-concrete combined section (2) is completed so as to complete the erection of the first section of steel beam;

s9: and repeating the step S8, and continuously moving the bridge girder erection machine (12) forwards to complete the assembly of the remaining standard sections (7) of the steel box girder.

2. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: in the S5, a transverse guide rail (8) is installed on a transverse support (6), the transverse guide rail (8) transversely extends to a longitudinal support (3), a longitudinal guide rail (9) is installed on the longitudinal support (3), the longitudinal guide rail (9) is connected with the transverse guide rail (8), the longitudinal guide rail (9) extends along the bridge direction, and in the moving process of the standard section (7), the transverse guide rail (8) is firstly transversely moved to the longitudinal support (3) and then longitudinally moved to the end part of the longitudinal support (3) along the longitudinal guide rail (9).

3. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: the lifting station (5) comprises two rows of transversely distributed support frames (51), the transverse support (6) is positioned between the two rows of support frames (51), and two sides of the transverse support (6) are respectively vertically connected to the inner sides of the two rows of support frames (51) in a sliding manner.

4. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: the lifting station (5) is provided with a lifting device (52) for lifting the transverse support (6).

5. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: and in the S6, after the supporting surface of the transverse bracket (6) is lifted to the designed height, the upright (11) below the transverse bracket (6) is lengthened upwards, and the upright (11) supports the supporting surface of the transverse bracket (6).

6. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: in the S8, a movable protection shed (14) is built on the highway (4), the movable protection shed (14) moves along the direction of the highway (4), and in the in-place installation process of the standard segment (7), the movable protection shed (14) moves to the position below the standard segment (7).

7. The cable-stayed bridge large-tonnage whole-section steel beam post-feeding type erection construction method according to claim 1, which is characterized in that: the S3 comprises the following steps:

s3.1: installing a jig frame on the longitudinal support (3), then assembling the steel box girder on the jig frame, dismantling the jig frame after the steel box girder is welded, and supporting the steel box girder on the longitudinal support (3) by using a distribution beam;

s3.2: binding steel bars and pouring bottom plate concrete of the steel-concrete combined section (2);

s3.3: after the bottom plate concrete reaches the designed strength, installing a counter-pulling structure on the top surface of the steel box girder, and applying a pretension force to each counter-pulling reinforcing steel bar to enable the steel-concrete combined section (2) to be fixedly connected with the lower cross beam of the main tower (1);

s3.4: and (3) erecting an internal mold in the steel-concrete combining section (2) and pouring web plate and top plate concrete.

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