基于云理论的斜拉索可靠性评价方法

为准确评估易损难修的斜拉索的可靠性,保证行车安全舒适,提出一种基于云理论的斜拉索可靠性评估方法.首先根据拉索力学特点和常见病害,以斜拉索的运营状态应力极值、恒载索力变幅、应力幅、基频、服役时间、PE护套开裂程度及阻尼系统完好程度为指标,建立了斜拉索可靠性评估指标体系.咨询专家意见建立权重云模型,并根据泛概念树的概念扩充原理实现权重的群决策.最后将指标对各等级的平均确定度与权重云模型加权汇总,得到可靠等级确定度的云模型并以此确定最终评级.规范评估结果与拉索实际病害情况对比验证了所提方法结果的合理性和可操作性.

Reliability Evaluation on Stay Cables Based on Cloud Theory

In order to accurately assess the reliability of the stay cables, which are vulnerable and difficult to repair, and to ensure a safety and comfort driving, a reliability evaluation method on stay cables based on cloud theory was proposed. According to the mechanical characteristics and common defects of cables, a reliability evaluation index system of stay cables was established by selecting indexes using the extreme stress value, amplitude of constant load, stress amplitude, basic frequency, service time, cracking degree of PE sheath and integrity of the damping system. Then the weight cloud models were established according to experts′ opinions, and the group decision weights were obtained from the concept extension of general concept tree. Finally, a weighted summary was conducted on the average certainty of assessment grade for each index and the weight cloud model. The certainty cloud models of each reliable grade thus can be obtained to determine the final result. The rationality and maneuverability of the method were verified by comparing the specification evaluation results with the actual defect condition.