基于加权倾角影响线的梁桥损伤识别方法

Damage Identification Method of Beam Bridge based on Weighted Angular Influence Line

为了利用倾角影响线进行损伤识别,由结构位移计算推导了简支梁支座处倾角影响线的解析式,提出加权倾角影响线的概念,将加权倾角影响线曲率指标作为标识量建立损伤识别理论。为了推广指标在连续梁中的应用,以两跨连续梁为例阐述了加权倾角影响线的构造方法。通过数值算例,设置多个损伤工况,对简支梁和连续梁进行损伤识别,再分析倾角测量精度对损伤识别结果的影响。结果表明:仅利用损伤后的倾角影响线信息,即可对桥梁结构进行损伤位置进行标定,指标对各个位置的损伤敏感性相同,可以对多点损伤进行有效识别,在现有的高精度倾角传感器分辨率下可以利用该指标进行损伤识别。

In order to identify beam bridge damage by using the angular influence line,the analytical formula of the angular influence line at the support of simply supported beam is derived from the calculation of structural displacement,the concept of weighted angular influence line is proposed,and the curvature index of weighted angular influence line is used as the identification quantity to establish the damage identification theory. In order to popularize the application of index in continuous beam,taking two span continuous beam as an example,the acquisition method of weighted inclination influence line is expounded. Through numerical examples,multiple damage cases are set up to identify the damage of simply supported beams and continuous beams, and then the influence of inclination measurement accuracy on the damage identification results is analyzed. The results show that: using the information of the inclination influence line after damage,the damage location of the bridge structure can be calibrated. The index has the same damage sensitivity to each location,and can effectively identify multi-point damage,under the existing high-precision inclination sensor resolution,the index can be used to identify damage.