摘要
利用移动荷载激励下获得桥梁某测点的时程响应数据,结合小波包时频分析的特点,引入频带内具有时序性的局部能量概念,并以此定义了一个单测点时的损伤指标;进一步为了提高指标的准确性及抗噪能力,提出了利用不同速度(不同周期)不同测点的时空信息融合技术来进行最终损伤判别及分析。以一弯桥为研究对象,建立有限元模型,通过瞬态分析方法进行桥梁移动荷载作用下的损伤识别模拟,利用选定测点的时程响应数据,验证该方法的可行性,并进一步进行了因素分析及抗噪能力研究。研究表明:所提出的单测点损伤指标适用于多损伤识别,损伤位置处指标数值大小与测点位置有关,测点离损伤越近,数值越大;一定范围内移动荷载速度对结果的影响不大;通过时空信息融合技术做最终损伤判别可以有效的提高损伤识别的精确度及抗噪能力。
According to the characteristics of wavelet packet time-frequency analysis,the concept of local energy with time sequence within a frequency band was introduced to propose a damage index to be used to detect the damage with the time-history response data of a single point of a curved bridge under moving load.In order to improve the index's correctness and its anti-noise ability,the temporal-spatial information fusion technology using the information of different measured points under different moving loads was developed to make the final damage detection.Taking a curved bridge as the study object,the finite element model was established to verify the feasibility of the proposed method.Then the factor analysis and the anti-noise ability of the method were studied.The results showed that the damage index of single point is applicable to detect multiple damages;the index value at the damage location is associated with the location of the measured;the results of damage detection change little with variation of moving load speed in a certain range;with the temporal-spatial information fusion technology to do the final damage identification,the accuracy and anti-noise ability of the damage identification can be effectively improved.
出处
《振动与冲击》
EI
CSCD
北大核心
2016年第11期138-145,共8页
Journal of Vibration and Shock
基金
国家自然科学基金面上项目(51378034)
北京市自然科学基金面上项目(8122007)
关键词
损伤识别
弯桥
移动荷载
小波包分析
频带局部能量
时空信息融合技术
damage identification
curved bridge
moving load
wavelet packet analysis
local energy of frequency band
temporal-spatial information fusion
