基于应变模态变化率的压力管道无损检测

Undamaged detection of pipe based on modal varied quotiety of strain

模态分析被广泛应用于大型工程结构的无损检测中 .用振动模态对压力管道进行损伤分析 ,可以根据压力管道的一维连续性质和横截面积性质 ,把应变表示为位移振动模态的函数 ,采用变化率的方法进行损伤识别 .应用这种方法对由于损伤而导致管道刚度轻微的变化进行数值模拟 ,可以明显检测出其损伤位置 .

The modal analysis method is now being widely used in the undamaged detections of the engineering structures, with which the authors can analyze the pressure pipe′s damages. For the damaged analysis of the pipe by using the mode, the strain of the pipe at different locations can be presented as the mode function of the displacement according to the character of the one dimensional continuity and the cross section, whose varied quotiety can be used to identify the damage. Then the slight change of the stiffness caused by the damage can be simulated by numerical value and the damaged position can also be identified obviously by using this method.