School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, Shenzhen University, Shenzhen 518060, China.
Sensors (Basel). 2018 Dec 16;18(12):4456. doi: 10.3390/s18124456.
Cables are the main load-bearing structural components of long-span bridges, such as suspension bridges and cable-stayed bridges. When relative slip occurs among the wires in a cable, the local bending stiffness of the cable will significantly decrease, and the cable enters a local interlayer slip damage state. The decrease in the local bending stiffness caused by the local interlayer slip damage to the cable is symmetric or approximately symmetric for multiple elements at both the fixed end and the external load position. An eigenpair sensitivity identification method is introduced in this study to identify the interlayer slip damage to the cable. First, an eigenparameter sensitivity calculation formula is deduced. Second, the cable is discretized as a mass-spring-damping structural system considering stiffness and damping, and the magnitude of the cable interlayer slip damage is simulated based on the degree of stiffness reduction. The Tikhonov regularization method is introduced to solve the damage identification equation of the inverse problem, and artificial white noise is introduced to evaluate the robustness of the method to noise. Numerical examples of stayed cables are investigated to illustrate the efficiency and accuracy of the method proposed in this study.
电缆是悬索桥和斜拉桥等大跨度桥梁的主要承重结构构件。当电缆中的钢丝发生相对滑移时，电缆的局部弯曲刚度会显著降低，电缆进入局部层间滑移损伤状态。对于固定端和外部荷载位置的多个元件，局部层间滑移损伤对电缆局部弯曲刚度的降低是对称的或近似对称的。本文引入了一种特征对灵敏度识别方法来识别电缆的层间滑移损伤。首先，推导出特征参数灵敏度计算公式。其次，将电缆离散化为考虑刚度和阻尼的质量-弹簧-阻尼结构系统，根据刚度降低程度模拟电缆层间滑移损伤的大小。引入 Tikhonov 正则化方法求解反问题的损伤识别方程，并引入人为白噪声来评估方法对噪声的鲁棒性。研究了斜拉索的数值算例，以验证本文提出的方法的效率和准确性。
