The abnormal mechanicalstate will cause the structural performance degradation of a suspension bridge. This paper presents a mechanical state inversion method for suspension bridges based on the measured intersection points of main cables using 3D laser scanning. First, based on the catenary, the mathematical model between the suspender force and the measured intersection points coordinates is established, and an accurate calculation method of suspender force is proposed. Then, an accurate calculation method for the internal force of suspension bridge components with abnormal suspender force is proposed to evaluate the structural performance. Numerical experiments show that the proposed method is accurate in theory. Finally, 3D laser scanning is used to capture the shape of the main cable, and an automated algorithm is developed to calculate the intersection point of the main cables precisely. The accuracy and reliability of the proposed method have been verified on a completed suspension bridge with a span of 808 m.

中文翻译：

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3D激光扫描既有悬索桥结构性能评价的力学状态反演方法

异常的力学状态会导致悬索桥的结构性能退化。本文提出了一种基于使用 3D 激光扫描测量的主缆交叉点的悬索桥机械状态反演方法。首先，基于悬链线，建立吊杆力与实测交点坐标之间的数学模型，提出一种精确的吊杆力计算方法。然后，提出一种具有异常吊力的悬索桥构件内力的精确计算方法，用于评估结构性能。数值实验表明，该方法在理论上是准确的。最后用3D激光扫描捕捉主缆的形状，并开发了一种自动算法来精确计算主缆的交点。所提方法的准确性和可靠性已在一座跨度为 808 m 的已完工悬索桥上得到验证。