桅杆结构竖向杆件损伤位置识别的时域方法

桅杆结构在工程上应用广泛,但破坏事故时有发生,竖向杆件是其损伤发生的主要部位之一。由于桅杆结构具有强非线性,已经发展得比较完善的基于频域的损伤识别方法不适用于桅杆结构,对其进行损伤诊断成为一大难题。本文利用桅杆结构长细比大、柔性强的特点,探讨了竖向杆件刚度变化与节点水平位移响应的关系,并提出了基于水平位移时程响应的竖向杆件损伤位置识别的指标,说明了竖向杆件损伤的时域识别步骤,通过几个数值算例证明该指标能对损伤的竖向杆件位置准确地进行识别,最后,分析了信号测量噪声对识别指标的影响。

Damage detection method for vertical bars of mast structure in time domain

The mast structure was widely used in engineering,but failure accidents frequently occurred.Among the accidents,vertical bars were the main failure parts of masts.As a result of the high non-linearity,the well-developed damage detection methods based on frequency domain can not be suited for the mast structure.Damage detection of the mast structures has become a difficult problem.Based on the slender and pliant characteristics of mast structure,this article discusses the relationship between the stiffness change of vertical bars and the horizontal displacement responses of nodes,proposes the detection index of bars locations with damage based on the transient horizontal displacement responses,and clarifies the detection process of vertical bars in time domain.And the numerical examples prove that the index put forward in this paper can accurately detect the location of damaged bars.Finally,the influence of signal measuring noise on the detection index is analyzed.