基 于 随 机 子 空 间 和 统 计 模 型 的 输 电 塔 损 伤 识 别

Aiming at transmission tower structure，a damage detection method based on statistical model combined stochastic subspace identification algorithm is given，where vibration responses of transmission tower are used to obtain statistical features and construct highly sensitive damage index in order to diagnosis damage of local components. Firstly，transient dynamic response signals are collected. Secondly，modal parameters are identified by stochastic subspace identification algorithm，nominal modal parameters are built accordingly and the residual vector is defined，which is related to the structural parameters variation. Finally，the sensitivity of the residual to structural parameters is calculated，and then the χ² statistic value of the residual sensitivity is constructed as the damage detection index. Through numerical simulation and field test，a full-scale transmission tower Is analyzed，the results show that the proposed method can effectively identify local components damage of transmission tower，such as bolt loosening and structural member failure.