基于COMAC曲率的桥梁损伤定位研究

Bridge Damage Localization Based on Curvature of COMAC

为实现桥梁损伤位置的识别,通过理论公式推导了模态坐标置信因子(coordinate modal assurance criteria,简称COMAC),同时结合模态曲率构建新的损伤指标DI。利用有限元软件ANSYS进行模态分析,提取模态振型计算损伤指标DI。为了评估环境因素对该方法的影响,在噪声干扰下通过对一简支梁进行实验来验证该方法的有效性。结果表明,在不同损伤程度、损伤位置以及噪声水平的影响下,该方法能够精准定位桥梁的损伤位置,且所提方法不易受环境因素的影响,更加符合实际工程的应用,为桥梁损伤位置的识别提供了新的解决思路。

In order to identify the damage location of the bridge,the feasibility of combining the coordinate modal assurance criteria(COMAC)and modal curvature for damage detection is derived through theoretical formulas.Based on COMAC and modal curvature,a new damage index DI is established.The finite element software ANSYS is used for modal analysis to extract the mode shape and calculate the damage index DI.At the same time,noise is added to the mode shape to determine the impact of environmental factors on the performance of the method.In order to further study the effectiveness of this method,an experiment is conducted on a simply supported beam.The results show that under the influence of different degrees of damage,damage locations and noise level,this method can accurately identify the damage location of the bridge,and the proposed method is not easily affected by environmental factors,which has the practical engineering application and provides a new solution for identifying the damage location of the bridge.