A walking jacking method for a large-span bottom-supported tied-rod steel arch bridge

Abstract

The present invention is a walking jacking method for a large-span bottom-supported tie-bar steel arch bridge; it includes making a jacking device: a jacking frame, an "L-shaped" jacking frame, a walking jacking device, a cushion beam, a guide beam, an arch support, and a counterweight; jacking operation: completing the assembly of the arch bridge and the guide beam in the assembly area, loading the walking jacking device, transferring the load, and removing the assembly frame; continuing to jack the arch bridge forward, when the bridge tail is about to leave the pier, adding a counterweight behind the bridge and laying it on the tail bridge deck; continuing to slide until the cantilever is maximum, at which time the end deflection is less than the cylinder stroke of the walking jacking device, and removing the rear counterweight; continuing to jack until the designed position along the bridge axis is reached, and the guide beam is removed; the pier device is turned 90 degrees, and the bridge body is slid vertically to the bridge to the designed position. The method assembles the steel arch bridge into a whole above the approach bridge in advance, and then uses "walking jacking sliding" to jack and slide the bridge to the designed position. This method can reduce the difficulty of construction and improve quality, safety and construction period.

Description

Technical Field

[0001] The invention relates to the technical field of steel structure construction, in particular to a walking jacking method for a large-span bottom-supported tied-rod steel arch bridge. Background Art

[0002] With the rapid development of urban transportation construction, steel bridges are widely used in urban bridge construction due to their excellent mechanical properties such as large span, diverse shapes and fast construction. However, the construction environment of urban bridges is complex and diverse, and the deadweight of steel bridge structures is large. If conventional block bulk is used, a large number of temporary pile supports must be set up in the river channel. The temporary support foundation in the river channel is difficult to handle, and there are great safety and quality risks in the construction of the project, which has a great impact on the construction period of the entire project. Summary of the invention

[0003] The purpose of the present invention is to overcome the above-mentioned defects and propose a walking jacking method for a large-span bottom-supported tie-bar steel arch bridge, which can reduce construction difficulty, improve construction quality and ensure safety.

[0004] In order to achieve the above object, the present invention is achieved as follows:

[0005] A walking jacking method for a large-span bottom-supported tied-bar steel arch bridge.

[0006] Step 1, manufacturing a pushing device: the pushing device comprises a pushing frame (1), an "L-shaped" pushing frame (2), a walking pusher (3), a cushion beam (4), a guide beam (5), an arch support (6), and a counterweight (7); wherein,

[0007] Pushing frame: The pushing frame is welded and assembled from steel pipes and steel plates. It is a lattice structure and is used to transfer the deadweight load of the steel arch bridge supported by the walking jacking device to the approach bridge piers. During the pushing process, a total of 4 groups of temporary supports are set up, which are respectively set on the 2nd to 5th axes and are located directly below the longitudinal beams on both sides of the steel arch bridge; each group of temporary supports is arranged with 2 pairs of pushing support lattice towers corresponding to the longitudinal beams of the bridge body, and each tower is arranged with 1 set of walking jacking equipment. A group of temporary supports has 2 sets of walking jacking equipment arranged side by side;

[0008] "L-shaped" jacking frame: The "L-shaped" jacking frame is assembled and welded from steel pipes and steel plates. Since the steel arch bridge needs to slide a certain distance along the vertical bridge after being pushed to the designated position along the longitudinal direction, a pair of "L-shaped" jacking frames are symmetrically arranged on the east and west sides of 6# and 7# piers. After being pushed to the designated position along the longitudinal direction, the jacking equipment is rotated 90° and then slid horizontally to the designed position.

[0009] Guide beam: The guide beam adopts a truss-type guide beam, which is composed of a lower chord, an upper chord, a vertical bar, a diagonal web and a tube truss crossbeam structure between the guide beams on both sides. The lower chord is a variable-section solid web beam, and the upper chord and diagonal web are H-shaped steel beams. Steel pipes are used to form a truss-type crossbeam between the guide beams to enhance the integrity and rigidity of the guide beam. The material is Q355B. During the top-pushing construction process, the structural system is constantly changing. The cross sections of the longitudinal beams and arch ribs must withstand alternating positive and negative bending moments during the movement. In order to reduce the internal force of the main structure during the top-pushing, a temporary steel guide beam is set at the front end of the main structure. The guide beam permanently reduces the cantilever length of the main structure, thereby reducing the peak value of the negative bending moment of the cantilever of the main structure. A 1:5 transition slope is set at the lower flange at the front end of the guide beam to guide the main structure to the pier, so as to facilitate the forward movement of the main structure.

[0010] Walking jack: Walking jack is a combined structure, one part of which is a horizontal sliding and load supporting device, which supports the deadweight load of the sliding member and provides driving force for the horizontal friction force generated during sliding. One end is connected to the reaction device in the form of a hinge point, and the other end is connected to the load replacement device; the other part is a sliding lifting and horizontal deviation correction device, which is a device for replacing the deadweight load of the structure and correcting the horizontal deviation of the member during sliding. The horizontal sliding, correction and lifting are all driven by hydraulic cylinders;

[0011] Pad beam: It is assembled and welded from steel plates. It is used to expand the contact surface between the walking jack and the steel arch bridge and to adjust the elevation of the jacking cylinder and the lifting cylinder in the walking jack;

[0012] Counterweight: During the pushing process, when the bridge tail is about to leave the 3# pier, the arch bridge is pushed forward until the cantilever reaches the maximum. The reaction force of the 4# pier is zero, and the anti-overturning performance cannot meet the requirements. To ensure that the front end of the guide beam can smoothly go up the 7# pier, a counterweight is added behind the bridge when the bridge tail leaves the 3# pier to ensure that the pushing structure meets the anti-overturning requirements.

[0013] Step 2: Pushing operation:

[0014] Step 2.1: Complete the assembly of the arch bridge and the guide beam in the assembly area, load the walking jack, transfer the load, and remove the assembly frame;

[0015] Step 2.2: Continue to push the arch bridge forward. When the bridge tail is about to leave the 3# pier, add a counterweight at the rear of the bridge. The counterweight weighs about 350 tons and is laid on the bridge deck at the rear.

[0016] Step 2.3, continue sliding until the cantilever is at its maximum. At this time, the downward deflection of the end is less than the stroke of the hydraulic cylinder of the walking jacking equipment, and the guide beam can be smoothly put on the 7# pier. After the guide beam reaches the 7# pier, remove the rear counterweight;

[0017] Step 2.4: Continue pushing until the designed position along the bridge axis is reached and remove the guide beam;

[0018] Step 2.5: Rotate the 6# and 7# pier equipment 90 degrees and slide the bridge vertically to the designed position.

[0019] The advantages or positive effects of the present invention compared with the prior art are as follows:

[0020] 1. The jacking equipment is small in size, light in weight, and has a large carrying capacity. It is particularly suitable for horizontal sliding of large-tonnage components and equipment in narrow spaces or indoors;

[0021] 2. It can push at multiple points at the same time to disperse the horizontal and vertical loads on the lower supporting structure;

[0022] 3. The push reaction force action point is very close to the sliding support point, and the installation requirements for the support system are low;

[0023] 4. The walking jack transmits force directly, and the positioning accuracy of components or equipment is high;

[0024] 5. Good working reliability and low failure rate;

[0025] 6. The equipment has a high degree of automation, convenient and flexible operation, good safety, high reliability, wide application and strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the steel arch bridge being pushed forward along the bridge.

[0027] Figure 2 It is a schematic diagram of the position relationship between the push tire frame and the walking pusher.

[0028] Figure 3 It is a schematic diagram of the walking type jacking equipment.

[0029] Figure 4 This is a schematic diagram of a push tire frame.

[0030] Figure 5 This is a schematic diagram of an "L-shaped" push tire frame.

[0031] Figure 6 Schematic diagram of the guide beam structure.

[0032] Figure 7 Schematic diagram of the connection node between the guide beam and the steel arch bridge.

[0033] Figure 8 Schematic diagram of lateral slip of steel arch bridge. DETAILED DESCRIPTION

[0034] The present invention is further described below by means of specific examples.

[0035] like Figures 1 to 8 As shown in the figure, a walking jacking method for a large-span bottom-supported tied-bar steel arch bridge is

[0036] Step 1, manufacturing a pushing device: the pushing device comprises a pushing frame (1), an "L-shaped" pushing frame (2), a walking pusher (3), a cushion beam (4), a guide beam (5), an arch support (6), and a counterweight (7); wherein,

[0037] Pushing frame (1): The pushing frame is welded and assembled from steel pipes and steel plates. The pushing frame is a lattice structure and is used to transfer the deadweight load of the steel arch bridge supported by the walking pusher to the approach bridge piers. During the pushing process, a total of 4 groups of temporary supports are arranged, which are arranged on the 2nd to 5th axes and are located directly below the longitudinal beams on both sides of the steel arch bridge. Each group of temporary supports is arranged with 2 pairs of pushing support lattice towers corresponding to the longitudinal beams of the bridge body. Each pair of towers is arranged with a set of walking pushing equipment. A group of temporary supports is arranged with 2 sets of walking pushing equipment side by side.

[0038] "L-shaped" jacking cradle (2): The "L-shaped" jacking cradle is assembled and welded from steel pipes and steel plates. Since the steel arch bridge needs to slide a certain distance along the vertical bridge direction after being pushed to the designated position along the longitudinal direction of the bridge, a pair of "L-shaped" jacking cradles are symmetrically arranged on the east and west sides of the 6# and 7# piers. After being pushed to the designated position along the longitudinal direction of the bridge, the jacking equipment is rotated 90° and then slid horizontally to the designed position.

[0039] Guide beam (5): The guide beam adopts a truss-type guide beam, which is composed of a lower chord, an upper chord, a vertical rod, a diagonal web and a pipe truss cross beam structure between the guide beams on both sides. The lower chord is a variable-section solid web beam, and the upper chord and the diagonal web are H-shaped steel beams. Steel pipes are used to form a truss-type cross beam between the guide beams to enhance the integrity and rigidity of the guide beam. The material is Q355B. During the top-pushing construction process, the structural system is constantly changing. The cross sections of the longitudinal beams and arch ribs must withstand positive and negative alternating bending moments during the movement. In order to reduce the internal force of the main structure during the top-pushing, a temporary steel guide beam is set at the front end of the main structure. The guide beam permanently reduces the cantilever length of the main structure, thereby reducing the peak value of the negative bending moment of the cantilever of the main structure. A 1:5 transition slope is set at the lower flange of the front end of the guide beam to guide the main structure to the pier, so as to facilitate the forward movement of the main structure.

[0040] Walking jack (3): The walking jack is a combined structure, one part of which is a horizontal sliding and load supporting device, which supports the deadweight load of the sliding member and provides driving force for the horizontal friction force generated during sliding. One end is connected to the reaction device in the form of a hinge point, and the other end is connected to the load replacement device; the other part is a sliding lifting and horizontal deviation correction device, which is a device for replacing the deadweight load of the structure and correcting the horizontal deviation of the member during sliding. The horizontal sliding, correction and lifting are all driven by hydraulic cylinders;

[0041] The cushion beam (4) is assembled and welded from steel plates and is used to expand the contact surface between the walking jack and the steel arch bridge and to adjust the elevation of the jacking cylinder and the lifting cylinder in the walking jack;

[0042] Counterweight (7): During the pushing process, when the bridge tail is about to leave the 3# pier, the arch bridge is pushed forward until the cantilever reaches the maximum. At this time, the reaction force of the 4# pier is zero. At this time, the anti-overturning performance cannot meet the requirements. To ensure that the front end of the guide beam can smoothly go up the 7# pier, a counterweight is added to the rear of the bridge when the bridge tail leaves the 3# pier to ensure that the pushing structure meets the anti-overturning requirements.

[0043] Step 2: Pushing operation:

[0044] Step 2.1: Complete the assembly of the arch bridge and the guide beam in the assembly area, load the walking jack, transfer the load, and remove the assembly frame;

[0045] Step 2.2: Continue to push the arch bridge forward. When the bridge tail is about to leave the 3# pier, add a counterweight at the rear of the bridge. The counterweight weighs about 350 tons and is laid on the bridge deck at the rear.

[0046] Step 2.3, continue sliding until the cantilever is at its maximum. At this time, the downward deflection of the end is less than the stroke of the hydraulic cylinder of the walking jacking equipment, and the guide beam can be smoothly put on the 7# pier. After the guide beam reaches the 7# pier, remove the rear counterweight;

[0047] Step 2.4: Continue pushing until the designed position along the bridge axis is reached and remove the guide beam;

[0048] Step 2.5: Rotate the 6# and 7# pier equipment 90 degrees and slide the bridge vertically to the designed position.

[0049] The advantages or positive effects of the present invention compared with the prior art are as follows:

[0050] 1. The jacking equipment is small in size, light in weight, and has a large carrying capacity. It is particularly suitable for horizontal sliding of large-tonnage components and equipment in narrow spaces or indoors;

[0051] 2. It can push at multiple points at the same time to disperse the horizontal and vertical loads on the lower supporting structure;

[0052] 3. The push reaction force action point is very close to the sliding support point, and the installation requirements for the support system are low;

[0053] 4. The walking jack transmits force directly, and the positioning accuracy of components or equipment is high;

[0054] 5. Good working reliability and low failure rate;

[0055] 6. The equipment has a high degree of automation, convenient and flexible operation, good safety, high reliability, wide application and strong versatility.

Claims

1. A walking jacking method for a large-span bottom-through tied-bar steel arch bridge, characterized in that: Step 1, manufacturing a pushing device: the pushing device comprises a pushing frame (1), an "L-shaped" pushing frame (2), a walking pusher (3), a cushion beam (4), a guide beam (5), an arch support (6), and a counterweight (7); wherein: Pushing frame: The pushing frame is welded and assembled from steel pipes and steel plates. It is a lattice structure used to transfer the deadweight load of the steel arch bridge supported by the walking pusher to the approach bridge piers. During the pushing process, 4 sets of temporary supports are set on the piers, along the axis of 2#~5# piers and directly below the longitudinal beams on both sides of the steel arch bridge; each set of temporary supports is arranged with 2 pairs of pushing frames, corresponding to the longitudinal beams of the bridge body, and each pair of pushing frames is arranged with 1 set of walking pushers. A set of temporary supports is arranged with 2 sets of walking pushers side by side; "L-shaped" jacking frame: The "L-shaped" jacking frame is assembled and welded from steel pipes and steel plates. Since the steel arch bridge needs to slide a certain distance along the vertical bridge direction after being pushed to the designated position along the longitudinal direction, a pair of "L-shaped" jacking frames are symmetrically arranged on the east and west sides of 6# and 7# piers. After being pushed to the designated position along the longitudinal direction, the walking jacking device is rotated 90° and then slid horizontally to the designed position. Guide beam: The guide beam adopts a truss-type guide beam, which is composed of a lower chord, an upper chord, a vertical bar, a diagonal web and a tube truss crossbeam structure between the guide beams on both sides. The lower chord is a variable-section solid web beam, and the upper chord and diagonal web are H-shaped steel beams. Steel pipes are used to form a truss-type crossbeam between the guide beams to enhance the integrity and rigidity of the guide beam. The material is Q355B. During the top-pushing construction process, the structural system is constantly changing. The cross sections of the longitudinal beams and arch ribs must withstand alternating positive and negative bending moments during the movement. In order to reduce the internal force of the main structure during the top-pushing, a temporary steel guide beam is set at the front end of the main structure. The guide beam is used to reduce the cantilever length of the main structure, thereby reducing the peak value of the negative bending moment of the main structure cantilever; a 1:5 transition slope is set at the lower flange of the front end of the guide beam to guide the main structure to the pier, so as to facilitate the forward movement of the main structure; Walking jacking device: Walking jacking device is a combined structure, one part of which is a horizontal sliding and load supporting device, which supports the deadweight load of the sliding member and provides driving force for the horizontal friction force generated during sliding. One end is connected to the reaction device in the form of a hinge point, and the other end is connected to the jacking tire frame; the other part is a sliding lifting and horizontal deviation correction device, which is a device for replacing the deadweight load of the structure and correcting the horizontal deviation of the member during sliding. The horizontal sliding, correction and lifting are all driven by hydraulic cylinders; Pad beam: It is assembled and welded from steel plates. It is used to expand the contact surface between the walking jack and the steel arch bridge and to adjust the elevation of the jacking cylinder and the lifting cylinder in the walking jack; Counterweight: During the pushing process, when the bridge tail is about to leave the 3# pier, the arch bridge is pushed forward until the cantilever reaches the maximum. The reaction force of the 4# pier is zero, and the anti-overturning performance cannot meet the requirements. To ensure that the front end of the guide beam can smoothly go up the 7# pier, a counterweight is added behind the bridge when the bridge tail leaves the 3# pier to ensure that the pushing structure meets the anti-overturning requirements. Step 2: Pushing operation: Step 2.1: Complete the assembly of the arch bridge and the guide beam in the assembly area, load the walking jack, transfer the load, and remove the assembly frame; Step 2.2: Continue to push the arch bridge forward. When the bridge tail is about to leave the 3# pier, add a counterweight of 350 tons at the rear of the bridge and lay it on the bridge deck at the rear. Step 2.3, continue sliding until the cantilever is the largest. At this time, the end deflection is less than the cylinder stroke of the walking jack, and the guide beam can be smoothly put on the 7# pier. After the guide beam reaches the 7# pier, remove the rear counterweight; Step 2.4: Continue pushing until the designed position along the bridge axis is reached and remove the guide beam; Step 2.5: Turn the walking jacks at piers 6# and 7# by 90 degrees and slide the bridge vertically to the designed position.

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