A construction method for dismantling a truss-type composite arch bridge

Abstract

The invention discloses a construction method for dismantling a truss-type composite arch bridge. The construction steps of this construction method are divided into three major parts: first, remove the bridge deck system, second, install the slings, and third, remove from the mid-span to the sides of the two arches in turn, first remove the side box of the solid web section, Then, remove the upper chord saddlebags, the oblique web rod, and the lower chord saddlebags of the fourth section, the third section, the second section, and the first section in sequence. In the construction method, the arch ring of the old bridge is lifted and supported by means of the CFST arch structure of the new bridge, the axial force of the arch structure is slowly released by setting a jack during the opening of the arch, and the side box is clamped by a vertical limit device. This ensures that the old bridge is stably converted from an independent system to two separate cantilever systems, which ensures the smooth demolition of the bridge.

Description

technical field [0001] The invention relates to a construction method for dismantling a truss-type composite arch bridge, and belongs to the technical field of bridge dismantling. Background technique [0002] Bridges are an important part of roads, and they are mainly erected on rivers, lakes and seas, as well as between adjacent mountains and streams. With the rapid growth of my country's economy, road transportation is also developing rapidly. Some bridges built two or three decades ago have been unable to transport demand, so new bridges need to be built to replace the old ones. Some of the old bridges need to be demolished, and the easiest and quickest way to demolish a bridge is to demolish it by blasting. However, not all old bridge demolition methods are suitable for blasting demolition. For example, some bridges erected in nature reserves, scenic reserves, drinking water areas, etc., if blasting demolition is used, it is easy to cause damage to the environment and...

AI Technical Summary

Problems solved by technology

However, after it is converted into two cantilever truss systems, the forces of the two systems cannot be mutually restricted. To a large extent, there will be a gap between the two systems due to the cutting seam during the separation cutting process or after the system is cut. The gap makes the two systems on both sides of the vault cutting seam appear relative displacement or even swing left and right. When the vault transitions from the closed state to the separated state, a large impact load will be generated instantaneously. This impact load may cause the two systems after separation to appear. collapse phenomenon

Moreover, after the bridge frame is cut into two separate cantilever truss systems, under its gravity, the cantilever truss system will have a tendency to deflect and move downward, which may also cause the two separated systems to collapse

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