由车辆响应识别桥梁固有频率

在车辆上安装传感器获取车辆过桥动力响应,进而识别桥梁固的有频率,是近年出现的测试桥梁动力特性的新型方法。该方法相比在桥上安装大量传感器获取桥梁动力响应去识别桥梁固有频率,无论是在安装还是测试都节省了大量的人力物力,且在测试当中不需要阻断交通。本文由车辆在简支梁上匀速移动的情况,理论推导了车辆频率与桥梁频率的关系,通过数值模拟和实桥试验,由车辆过桥的振动响应,识别出了桥梁的一阶固有频率。

Study on Extracting Bridge Dynamic Characteristics from the Dynamic Response of A Passing Vehicle

Installing the sensors on the vehicle to obtain the dynamic response,and then identifying the natural frequencies is a new method to test the bridge dynamic characteristics in recent years.Compared with the method of installing a large number of sensors on the bridge,the new method needs less human and material resources without obstructing the traffic.Based on such an approach,the simply supported beams under the moving vehicle with uniform speed have been studied in the present paper.The first natural frequency can be extracted from the frequency spectrum by Fast Fourier Transform(FFT) of the vehicle acceleration response with making the vehicle to be the excitation and the signal supply.