基于MIDAS多工况模拟的体外预应力加固技术应用研究OA

With the prosperity and development of China's economy,the rapid growth of traffic flow poses a severe challenge to the structural safety of old bridges.In this paper,taking a continuous box gird-er bridge in the south approach of a Yangtze River Bridge as the object of study,aiming at a variety of crack diseases caused by the lack of effective maintenance due to long-term operation,the cause of the dis-ease was determined by field detection and finite element analysis,such as the loss of steel bundle prestress and the degradation of structural performance.The applicability of different reinforcement technologies was comprehensively analyzed,and a reinforcement scheme for arranging external prestressed steel bundles inside the box girder was proposed.This scheme not only significantly improves the stress state of the bridge span structure,increases its bearing capacity by about 17.26％,but also greatly reduces the tensile stress level of the bridge span by up to 50.80％,effectively eliminating the structural safety hazards and ensuring the safe operation of the bridge.