Sekiya Hidehiko, Kimura Kentaro, Miki Chitoshi
Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Setagaya 158-0082, Japan.
Urban and Civil Engineering, Tokyo City University, 1-28-1 Tamazutsumi, Setagaya 158-8557, Japan.
Sensors (Basel). 2016 Feb 19;16(2):257. doi: 10.3390/s16020257.
In bridge maintenance, particularly with regard to fatigue damage in steel bridges, it is important to determine the displacement response of the entire bridge under a live load as well as that of each member. Knowing the displacement response enables the identification of dynamic deformations that can cause stresses and ultimately lead to damage and thus also allows the undertaking of appropriate countermeasures. In theory, the displacement response can be calculated from the double integration of the measured acceleration. However, data measured by an accelerometer include measurement errors caused by the limitations of the analog-to-digital conversion process and sensor noise. These errors distort the double integration results. Furthermore, as bridges in service are constantly vibrating because of passing vehicles, estimating the boundary conditions for the numerical integration is difficult. To address these problems, this paper proposes a method for determining the displacement of a bridge in service from its acceleration based on its free vibration. To verify the effectiveness of the proposed method, field measurements were conducted using nine different accelerometers. Based on the results of these measurements, the proposed method was found to be highly accurate in comparison with the reference displacement obtained using a contact displacement gauge.
在桥梁维护中，特别是对于钢桥的疲劳损伤，确定整个桥梁在活载作用下以及每个构件的位移响应非常重要。了解位移响应能够识别可能导致应力并最终导致损伤的动态变形，从而也能够采取适当的对策。理论上，位移响应可以通过对测量加速度进行两次积分来计算。然而，加速度计测量的数据包含由模数转换过程的局限性和传感器噪声引起的测量误差。这些误差会使两次积分的结果失真。此外，由于在役桥梁会因过往车辆而持续振动，因此难以估计数值积分的边界条件。为了解决这些问题，本文提出了一种基于桥梁自由振动从其加速度确定在役桥梁位移的方法。为了验证所提方法的有效性，使用了九个不同的加速度计进行现场测量。基于这些测量结果，发现与使用接触式位移计获得的参考位移相比，所提方法具有很高的准确性。
