Calculation And Analysis For Cable Replacement Work Of Qianwei Minjiang Bridge

During recent decades cable-stayed bridges are booming in the field of bridge construction,however,because of antisepsis of cables and construction technique problems,many constructed cable-stayed bridges will be faced the problem of being replaced cables soon or later.In this thesis,the construction and monitoring general method of cable replacement work for Qianwei Minjiang River cable-stayed bridge is introduced firstly,then,using large-scale commercial finite elements analysis software,Algor,a space solid model is developed. In order to give attention to internal force and deformation,the thesis simulates the factual situation of the bridge by adding boundary elements. The analyzed items include:cable forces,deflections,stress of box-girder and maximum horizontal deformation of tower under different cable-replacement cases,which can be used to tutor design and construction for other similar works. As a result,while some stayed-cables are released,the cable forces of remaining and neighboring 2 or 3 groups increase remarkably,but the others do not,the box-girder puts up the characteristic of biggish stiffness which stress variety isn't marked.In order to ascertain the character of cable-replaced bridge,in addition,the thesis calculates mode shapes and natural frequencies of the bridge using Algor software and estimates the result of dynamic load test and calculation in details.This thesis will accumulate more experiments for design and dynamic load test for cable-replacement works.