不同质量矩阵对桥梁自振特性的影响分析

Influence of different quality matrix on natural vibration characteristic of bridges

利用有限元方法进行结构自振特性分析时需要选用适当的单元质量矩阵模式.采用一致质量矩阵和堆聚质量矩阵对几座典型结构的大跨度桥梁的自振特性进行了分析.计算结果表明,一致质量矩阵与堆聚质量矩阵对具有空间质量分布的桥跨结构影响较大,对于大型结构复杂桥梁的动力分析宜采用一致质量矩阵模型计算.所得的结果对分析桥梁的自振特性具有重要的工程实用价值.

Correct quality matrix will be used to analyze the natural vibration characteristic with finite element method . This paper calculates the natural vibration frequencies of several wide-span bridges by using lumped quality matrix and consistent quality matrix. The result shows that it is different to analyze the bridges of three - D quality with lumped quality matrix and consistent quality matrix, and it is correct to analyze dynamic characteristic of large and complicated bridges by using consistent quality matrix. The obtained analysis results have great practical values for the analysis of natural vibration characteristic of related engineering structures.