摘要
以桥梁结构有限元为工具,把当前结构模型中各单元的等效面积、惯性矩以及板壳单元的厚度作为识别参数{p},建立识别参数对于各种量测的灵敏度矩阵[S{p}]。同时以测取的结构某些部位的位移、应变以及低阶的振动模态参数为基准,与原先结构的分析结果进行比较建立综合误差向量{ΔE}。通过优化方法不断调整当前计算模型的参数{ΔP}使结构响应与相应的试验值最大程度地吻合({ΔE}小到一定量级),从而得到结构参数变化的信息。以此为基础即可实现桥梁结构的损伤判别以及承载能力的评估。
A new algorithm based on bridges FEA modal and combined data of static and modal tests is developed for structural damage evaluation. In this approach, the nominal area or inertia moment of beam elements or thickness of shell elements are selected as system parameter for identification. The incomplete sets of data from static and modal tests are used to establish structure response error function {Δ E } with comparison of previous results. Meanwhile, sensitivity matrix [ S ] about system parameter to measurement information is also formulated. By applying optimal methods such as Gauss Newton and gradient, original structural parameter could be adjusted step by step to make the computational response of current model be close to measurement. As a result, the current conditions of structure are reflected by the adjusted parameter. Based on the actual parameter, bridge damage detection and load carrying capacity evaluation could be performed reliably.
出处
《中南公路工程》
2005年第2期23-26,141,共5页
Central South Highway Engineering
基金
国家自然科学基金资助项目(59878037)
