Setting technology of second-phase pre-stressed tendons in straddle type single-traffic-track girder bridge

Abstract

The invention relates to a setting technology of second-phase pre-stressed tendons in a straddle type single-traffic-track girder bridge, and belongs to the technical field of bridge engineering. The setting technology of the second-phase pre-stressed tendons in the straddle type single-traffic-track girder bridge is applied to all sorts of straddle type single-track traffic such as light-sized straddle type single-track traffic, middle-sized straddle type single-track traffic and heavy-sized straddle type single-track traffic. A simple support change continuous system or a simple support change rigid framework system or a simple support change continuous rigid framework system is adopted in the straddle type single-track traffic, after system transformation, curve-type second-phase pre-stressed tendons with the general length are arranged in a series of N spans of the track girder bridge, and second-phase pre-stressing force is applied. The second-phase pre-stressed tendons not only need to be arranged in a hogging moment area of the wet joints of secondary abutment piers and middle piers but also need to be arranged in a sagging moment area of the wet joints of the secondary abutment piers and the middle piers. The setting technology of the second-phase pre-stressed tendons in the straddle type single-traffic-track girder bridge effectively solves the problems that large tensile stress can be generated easily on the anchoring outer sides of the second-phase pre-stressed tendons in an upper structure of a bridge, and the phenomena of cracking and crack propagation can happen, the durability of the structure is improved, construction is convenient, construction period is short, and obvious economical efficiency is achieved.

Description

technical field [0001] The invention belongs to the field of straddle-type monorail traffic, and relates to a second-stage prestressed tendon in a track girder bridge with prefabricated and then assembled, simply supported and then continuous, or simply supported and then rigid structure, or simply supported and then continuous rigid structure system. Setting technology for all straddle monorails, light, medium and heavy. Background technique [0002] Straddle-type monorail transit adopts prefabrication before assembly, first simply supported and then continuous, or first simply supported and then rigid frame, or first simply supported and then continuous rigid frame system, which has many advantages: it can minimize the expansion joints on the straddle monorail transit line and the number of supports, reduce the wear on the rubber tires of the train, enhance the smoothness of the line, prolong the service life of the vehicle, and reduce operation and maintenance costs. [...

AI Technical Summary

Problems solved by technology

There are many problems in adopting this second-stage prestressed tendon setting technology. The superstructure of the bridge is prone to generate large tensile stress outside the anchorage of the second-stage prestressed tendons, and cracks and cracks will expand, which will affect the durability of the structure. Stress tendons must be stretched in sections, and the number of stretches is too many, which affects the construction period

[0004] In view of the problems existing in the installation of the second-stage prestressed tendons of the existing simple-support variable continuous system track girder bridge, it is urgent to study a technology for setting the second-stage prestressed tendons in the straddle-type monorail transit track girder bridge, so as to effectively solve the problem of the upper part of the bridge. The structure is prone to large tensile stress, cracking and crack expansion outside the anchorage of the second-stage prestressed tendons

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