基于跨中位移影响线的箱梁损伤定位研究

摘要

为了实现箱梁桥的损伤定位，利用梁式桥结构损伤必然影响弯曲刚度，则梁体跨中挠度影响线将不再以跨中为轴对称分布这一特点，提出了以桥梁损伤前后跨中挠度影响线三次差值为指标的损伤定位方法。对一座简支箱梁桥按照单一部位损伤和多部位同时损伤予以分析计算，在预设损伤部位均出现了损伤指标的明显突变，表明该方法对箱梁的单部位和多部位损伤定位具有较好的适用性。%In order to realize the damage location of the box girder bridge,a damage location method is proposed by using the characteristics of the girder bridges damage will inevitably affect the bending rigidity and the influence line of the mid-span deflection of the beam will no longer be symmetrical,which is the third difference of the influence line of the mid-span deflection before and after the bridge damage. A simple supported box girder bridge with single site and multiple sites damage condition were analyzed and calculated,then the damage index of the preset position was found to have a significant mutation. T he results show that the method is applicable for single site and multiple sites damage condition location of the box girder.