摘要
提出了基于静态弯曲的静定梁两阶段损伤识别方法.首先,分别给出了利用梁弯曲的测量挠度和测量应变计算曲率的公式,提出了根据梁损伤前后的相对曲率差识别损伤位置的方法;在此基础上,给出了利用模拟退火算法确定损伤程度的方案,从而完成静定梁的损伤位置和程度的识别.为验证所提方法的正确性和有效性,数值模拟了简支梁的损伤识别,考察了损伤位置和程度以及测量噪声等对损伤识别结果的影响.数值算例结果表明:损伤位置的首先确定减少了损伤程度识别过程中的损伤状态参数;噪声对基于测量挠度的损伤定位影响较基于测量应变的损伤定位影响更为显著;当测量噪声不超过5%时,损伤程度识别结果具有较高的精度和较强的鲁棒性.
A two-stage damage identification method of statically determinate beam based on static bending is established. First, the formulas for calculating the bending curvature of beam by the measurement deflection and the measurement strain are given, and then a method for determining the damage location based on the relative curvature difference of curvatures of the damaged and undamaged beam is proposed. On this basis, a scheme of quantifying the damage degree of beam using the simulated annealing algorithm is proposed. Thus, identification of the damage location and its degree of the statically determinate beam is achieved. In order to validate the proposed method, damage identification of a simply-supported beam is conducted by a numerical simulation, and the influences of the damage location, damage degree and measurement noise on the damage identification are examined numerically. It is revealed from the numerical results that the determination of damage location in advance reduces the damage parameters in the process of damage degree identification, and the influence of measurement noise on damage location identification based on the measured deflection is more significant than that based on the measured strain. Furthermore, when the measurement noise is less than 5%, the identification results of damage degree have higher accuracy and robustness.
出处
《力学季刊》
CSCD
北大核心
2017年第4期710-721,共12页
Chinese Quarterly of Mechanics
关键词
静定梁
损伤识别
相对曲率差
模拟退火算法
鲁棒性
statically determinate beam
damage identification
relative curvature difference
simulated annealing algorithm
robustness
