CN115679844A - Integrated dismantling method for steel pipe concrete arch bridge - Google Patents

Abstract

The invention relates to a method for integrally dismantling a concrete-filled steel tube arch bridge, which comprises the following steps: A. the arch rib is pulled by using the diagonal draw buckle cable; B. breaking the midspan; C. dismantling the suspender; D. removing the arch rib; E. newly building a main arch ring, reserving a cable crane and a cable fastening system used for bridge demolition, and replacing the new main arch ring by adopting the cable crane and cable fastening system; F. and (3) sequentially completing installation and replacement of the main arch ring, the bridge deck system, the suspender and the cross beam, completing construction of the main arch ring and the suspender, and completing new construction of the bridge. In the cable hoist and mount demolishs the scheme, the cable hoist system is installed promptly when carrying out the bridge floor system and demolishs, and the arch-mounted building all can use the cable system with the arch ring demolishs, and simultaneously, if newly-built bridge adopts the form that does benefit to hoist and mount, also can utilize the cable to hang and carry out the construction. Greatly saving the cost and the construction period.

Description

Integrated Demolition Method for Concrete Steel Tube Arch Bridge

technical field

The invention relates to an integrated demolition method for the demolition and construction of a steel pipe concrete arch bridge.

Background technique

With the development of the economy, my country has built a number of world-class long-span rigid arch bridges, such as Shanghai Lupu Bridge and Chongqing Chaotianmen Bridge. With the development of science and technology and the emergence of cement, the construction of reinforced concrete and prestressed concrete arch bridges has reached a climax. However, with the emergence of larger span bridges, the problems of self-weight and construction erection of reinforced concrete arch bridges and prestressed concrete arch bridges have become more and more prominent. Part of the superstructure of concrete-filled steel tube arch bridges is facing the end of demolition and replacement.

Traditional demolition construction method 1: Traditional demolition schemes are based on low cost considerations. They are blasting and mechanical demolition methods, which only consider structural demolition, and often consider new construction and erection systems after demolition is completed, which is a huge waste of resources. Traditional demolition construction method 2: Erection of steel support bent frames under the bridge + large truck crane demolition method. This scheme is greatly restricted by the terrain. For large-span bridges in mountainous areas, it is difficult to install steel support bent frames at the lower part of the bridge, and the bridge elevation is high, so large-scale hoisting equipment cannot be located on the ground. The demolition scheme has great limitations and is not suitable for rebuilding the CFST bridge in situ.

Contents of the invention

One of the purposes of the present invention is to provide an integrated demolition method for concrete-filled steel tube arch bridges in order to overcome the deficiencies in the prior art.

To achieve the above object, the present invention is achieved through the following technical solutions:

An integrated dismantling method for demolition and construction of a steel pipe concrete arch bridge, characterized in that it comprises the steps of:

A. Use the cable-stayed buckle to pull the arch rib;

B. The mid-span is interrupted, and the longitudinal and horizontal beams of the bridge deck are removed; it is removed in the direction from the mid-span to the top of the pier; each time a span longitudinal beam is removed, then the cross beam is removed;

C. Remove the suspender, fix the beam to be removed by cable hoisting and reduce the force on the suspender, then cut the suspender, and hoist the beam and suspender away after the suspender is cut;

D. Remove the arch rib. Before removing the arch rib, use the cable-stayed buckle system to adjust the internal force of the main arch rib, so that the internal force of the mid-span section of the vault is zero; then use cutting equipment such as wire saws to cut the arch rib along the vault section , so that the structural system is converted from an arch structure to a cantilever system, and the demolition of the arch rib structure is completed according to the division of segments, and the arch ribs are removed in the order from the mid-span to both sides;

E. Newly build the main arch circle, retain the cable hanger and buckle system used for bridge demolition, and use the cable hanger system to replace the new main arch circle;

F. Complete the installation of the main arch ring, bridge deck system, suspenders, beams, and replacement of the bridge deck in sequence. The construction of the main arch ring and suspenders is completed, and the bridge is newly built.

The integrated demolition method of the steel pipe concrete arch bridge in the present invention solves the problem of synchronous construction of the steel pipe concrete arch bridge. The dismantling sequence follows the law of "from top to bottom, breaking into parts" and the principle of "symmetry and balance".

In order to ensure the safety of the bridge demolition process, so that the arch ring will not be damaged due to excessive local stress during the tensioning process of the buckle cable, the stress situation of the entire arch ring is checked and analyzed.

Use the cable hook to remove it gradually from the outside to the inside in the horizontal direction, and the upstream and downstream are symmetrical during the demolition; the longitudinal removal is symmetrical from the middle span to the bridge heads on both sides. After the main arch ring is cut into sections by cutting method, it is hoisted by cable;

The cable hoisting and dismantling does not need to close the channel when removing the upper structure and arched buildings. In order to ensure safety when hoisting the arch ring, the hoisting span needs to temporarily close the channel. The closing time is about 1 to 2 hours, and other unconstructed spans do not need to be closed During the entire demolition period, there is little impact on the passage of the channel.

In the cable hoisting and dismantling scheme, the cable crane system is installed during the demolition of the bridge deck system. The cable system can be used for the construction on the arch and the demolition of the arch ring. construction. Greatly save cost and construction period.

Description of drawings

Fig. 1 is the state schematic diagram after step A of the present invention is finished;

Fig. 2 is a schematic diagram of the state after step B of the present invention is completed.

Fig. 3 is a schematic diagram of the state after step C of the present invention is completed.

Fig. 4 is a schematic diagram of the state after step D of the present invention is completed.

Fig. 5 is a schematic diagram of the state after step E of the present invention is completed.

Fig. 6 is a schematic diagram of the state after step F of the present invention is completed.

Detailed ways

An integrated dismantling method for demolition and construction of a steel pipe concrete arch bridge, characterized in that it comprises the steps of:

A. As shown in Figure 1, use the cable-stayed buckle cable 1 to pull the arch rib 2;

B. As shown in Figure 2, the middle of the span is interrupted, and the longitudinal and horizontal beams of the bridge deck are removed; according to the direction from the middle of the span to the top of the pier, the longitudinal beam 3 of each span is removed, and then the cross beam 4 is removed;

C, as shown in Figure 3, remove the boom 5, use the cable hanger 6 to fix the crossbeam 4 to be removed and reduce the stress on the boom 5, then cut the boom 5, hang the crossbeam 4 after the cut of the boom 5 is completed and boom 5;

D. As shown in Figure 4, remove the arch rib 2. Before removing the arch rib 2, use the cable-stayed buckle 1 system to adjust the internal force of the main arch rib 2, so that the internal force of the mid-span section of the vault is zero; then use a wire saw to cut The equipment cuts the arch rib 2 along the section of the vault, so that the structural system is converted from the arch structure to the cantilever system, and the demolition of the arch rib structure is completed according to the segment division, and the arch rib 2 is removed in the order from the middle of the span to the two sides;

E, as shown in Figure 5, build main arch circle 11, retain the cable hanger 6 that bridge dismantling uses, cable-stayed buckle 1, adopt the cable hanger 6 buckle system to replace new main arch circle 11;

F. As shown in Figure 6, the installation of the main arch ring 11, bridge deck system 12, suspenders and crossbeams, and replacement of the bridge deck are completed in sequence. The construction of the main arch ring and suspenders is completed, and the bridge is newly built.

The integrated demolition method of the steel pipe concrete arch bridge in the present invention solves the problem of synchronous construction of the steel pipe concrete arch bridge. The dismantling sequence follows the law of "from top to bottom, breaking into parts" and the principle of "symmetry and balance".

In order to ensure the safety of the bridge demolition process, so that the arch ring will not be damaged due to excessive local stress during the tensioning process of the buckle cable, the stress situation of the entire arch ring is checked and analyzed.

Use cable cranes to dismantle gradually from the outside to the inside in the horizontal direction, and the upstream and downstream are symmetrical during the dismantling; the longitudinal dismantling is symmetrical from the middle span to the bridge heads on both sides. After the main arch ring is cut into sections by cutting method, it is hoisted by cable;

The cable hoisting and dismantling does not need to close the channel when removing the upper structure and arched buildings. In order to ensure safety when hoisting the arch ring, the hoisting span needs to temporarily close the channel. The closing time is about 1 to 2 hours, and other unconstructed spans do not need to be closed During the entire demolition period, there is little impact on the passage of the channel.

In the cable hoisting and dismantling scheme, the cable crane system is installed during the demolition of the bridge deck system. The cable system can be used for the construction on the arch and the demolition of the arch ring. construction. Greatly save cost and construction period.

In the integrated dismantling method of the steel pipe concrete arch bridge in the present invention, after the steel-concrete superstructure is dismantled, the original bridge pier structure can also be used to rebuild the steel-concrete superstructure.

The above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement or improvement within the spirit of the present invention is covered by the claims of the present invention.

Claims (1)

1. A method for integrally dismantling a steel pipe concrete arch bridge is characterized by comprising the following steps:

A. the arch rib is pulled by using a diagonal pull buckle cable;

B. breaking the midspan, and dismantling the longitudinal beam of the bridge deck system; dismantling the bridge from midspan to pier top; when a span longitudinal beam is removed, a cross beam is removed;

C. dismantling the suspender, fixing the beam to be dismantled by utilizing cable hoisting, reducing stress of the suspender, then cutting the suspender, and hoisting the beam and the suspender after the suspender is cut;

D. removing the arch rib, and adjusting the internal force of the main arch rib by using a diagonal cable system before removing the arch rib to ensure that the internal force of the cross-section of the arch crown is zero; cutting the arch rib along the section of the arch crown by cutting equipment such as a rope saw and the like to convert the structure system from an arch structure into a cantilever system, completing the dismantling of the arch rib structure according to the section division, and dismantling the arch rib from the midspan to the two sides;

E. newly building a main arch ring, reserving a cable crane and a cable fastening system used for bridge demolition, and replacing the new main arch ring by adopting the cable crane and cable fastening system;

F. and (3) sequentially completing installation and replacement of the main arch ring, the bridge deck system, the suspender and the cross beam, completing construction of the main arch ring and the suspender, and completing new construction of the bridge.

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