基于静载试验进行桥梁结构损伤识别

Bridge Structural Damage Identification Based on Static Test

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}]。测取结构某些部位的位移、应变以及低阶的振动模态参数,以此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,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。

The equivalent area, inertia moment and plate\|shell thickness of all elements of the current model are selected as system parameter for identification {p}, using the finite element method of bridge structure in order to formulate sensitivity matrix  about the system parameter to measurement information. The displacement, strain and low\|order vibration mode parameters at certain parts of the bridge structure are measured and compared to the analytical results of the original structure to establish the composition error vector {ΔE}. With optimal methods like Gauss\|Newton and gradient, the structural parameter {ΔP} of the current computational model will be adjusted step by step to make the computational structural response be close to the test values to the maximum, thus the information of structural parameter variation will be obtained. On the basis of said study, the bridge structural damage identification and load\|carrying capacity evaluation could be done reliably.