摘要
针对结构中同时存在未知损伤和荷载的情况,基于虚拟变形法(VDM)发展一种两者共同识别的时域方法。VDM方法利用虚拟变形模拟结构损伤,可快速计算模型改变后的响应。该文首先结合有限元理论把VDM方法拓展到具有多个单元变形的结构中;然后考虑结构存在未知荷载时,利用未损伤理论模型同时识别荷载和虚拟变形,继而由虚拟变形和单元实际变形的关系来识别判断损伤类型和识别损伤大小;最后通过一个悬臂梁的试验进行方法验证,试验中未知荷载和损伤(包括其类型和大小)均能够被有效识别,并利用提出的移动时间窗和荷载形函数方法实现损伤与荷载的在线识别。
Unknown structural damages and loads usually coexistent together. Aiming at this problem, this paper develops a practical method in a time domain for their coexistent identification based on Virtual Distortion Method （VDM）. In VDM, virtual distortions are introduced to simulate structural damages, and responses of the damaged structure can be estimated quickly. This article firstly extends VDM into real structures with multiple element distortions using finite element theory, and then unknown loads and virtual distortions are reconstructed simultaneously via the measurements and an intact structural model. Then the damage extent and type are recovered by a relation between the virtual and actual distortions. A damaged cantilever aluminum beam is used in the experimental verification. Both load and damage （extent and type） are successfully identified. The identification is performed off-line as well as online by the application of a moving time window and a load shape function.
出处
《工程力学》
EI
CSCD
北大核心
2012年第12期316-321,348,共7页
Engineering Mechanics
基金
国家自然科学基金项目(50579008
51108066)
波兰科学家TEAM基金项目(TEAM/2008-1/4)
欧洲地区发展基金项目(POIG.0101.02-00-013/08-00)
关键词
结构健康监测
虚拟变形法(VDM)
荷载识别
损伤识别
荷载形函数
structural health monitoring
virtual distortion method
load identification
damage identification
load shape function
