Department of Electrical Energy, Metals, Mechanical Constructions, and Systems, Faculty of Engineering and Architecture, Ghent University, 9000 Gent, Belgium.
Department of Bridge and Tunnel Engineering, Faculty of Civil Engineering, University of Transport and Communications, Hanoi, Vietnam.
Sensors (Basel). 2018 Nov 26;18(12):4131. doi: 10.3390/s18124131.
Vibration-based structural health monitoring (SHM) for long-span bridges has become a dominant research topic in recent years. The Nam O Railway Bridge is a large-scale steel truss bridge located on the unique main rail track from the north to the south of Vietnam. An extensive vibration measurement campaign and model updating are extremely necessary to build a reliable model for health condition assessment and operational safety management of the bridge. The experimental measurements are carried out under ambient vibrations using piezoelectric sensors, and a finite element (FE) model is created in MATLAB to represent the physical behavior of the structure. By model updating, the discrepancies between the experimental and the numerical results are minimized. For the success of the model updating, the efficiency of the optimization algorithm is essential. Particle swarm optimization (PSO) algorithm and genetic algorithm (GA) are employed to update the unknown model parameters. The result shows that PSO not only provides a better accuracy between the numerical model and measurements, but also reduces the computational cost compared to GA. This study focuses on the stiffness conditions of typical joints of truss structures. According to the results, the assumption of semi-rigid joints (using rotational springs) can most accurately represent the dynamic characteristics of the truss bridge considered.
基于振动的大跨度桥梁结构健康监测（SHM）近年来已成为一个主导的研究课题。Nam O 铁路桥是一座位于越南南北向独特主轨上的大型钢桁架桥。为了对桥梁的健康状况评估和运营安全管理建立可靠的模型，进行广泛的振动测量活动和模型更新是非常必要的。实验测量是在环境振动下使用压电传感器进行的，并在 MATLAB 中创建了一个有限元（FE）模型来表示结构的物理行为。通过模型更新，将实验和数值结果之间的差异最小化。为了成功进行模型更新，优化算法的效率至关重要。采用粒子群优化（PSO）算法和遗传算法（GA）来更新未知的模型参数。结果表明，PSO 不仅提供了数值模型与测量值之间更好的精度，而且与 GA 相比还降低了计算成本。本研究侧重于桁架结构典型节点的刚度状况。根据结果，假设半刚性节点（使用旋转弹簧）可以最准确地表示所考虑的桁架桥的动力特性。
