固支梁振型与损伤关系的试验模态分析

Experimental Modal Analysis for the Relationship between Solid Structbeam Vibration Type and Damage

结构的动力特性和结构参数直接相关,结构的损伤将引起相应动力特性的改变。因此,如果能建立结构动力特性变化与结构损伤之间的映射关系,则可以利用结构振动测试信息实现结构损伤识别。按照采用数据和识别原理的不同,大致可以分为基于频率的方法、基于振型的方法、基于模态柔度的方法以及基于神经网络的方法等,但是在大型土木工程结构的测试中,一般只能获得低阶模态及不完备的自由度测试信息。

The dynamic characteristic of structures has a direct relationship with structural parameters, and structural damage can cause dynamic characteristics shifts correspondently. Therefore, if the mapping relation between structural damage and dynamic characteristic shifts can be established, the structural damage can be diagnosed by Using dynamic measurements. According to the measured data and identification principle, the identification methods can he divided into the method based on frequency, mode shape, modal flexibility and neural network and so on. Whereas, only lower modes and incomplete DOF （degree of freedom） measurement information can be obtained in the structural testing of large-scale civil engineering.