PC简支梁铁路桥墩身动力响应的特解边界元分析

根据特解边界元理论,建立动态响应数值分析方法,编制相应的动力分析程序,计算PC简支梁桥墩顶纵向位移、速度和加速度时程,详细分析其动态变化过程;采用有限元分析方法,选择8节点块单元模拟墩身,并与特解边界元的计算结果进行对比。结果表明:两者具有较好的一致性,说明采用特解边界元的数值处理方法和所构造的边界元计算墩身动力响应是正确的。由于边界单元法只在边界上剖分单元,通过基本解把域内未知量化为边界未知量求解,自由度数目大大减少,计算效率较高。

Dynamic Response Analysis of Railway Bridge Pier of Simply Supported PC Beam with Particular Solution Boundary Element Method

According to the theory of BEM using particular solution, the paper establishes the numeric (simulation) method of dynamic response and works out the program of corresponding dynamic interaction. The time history of longitudinal displacement, velocity and acceleration on the pier of PC simple supported beam bridge is calculated and its dynamic variation process is analyzed in detail. Using brick element of eight nodes, the FEM model for pier dynamic analysis is built. The effectiveness of the BEM using particular solution (proposed) in this paper is demonstrated through comparison of the obtained results with those derived from FEM. The computing efficiency is excellent with BEM since the elements are divided only on the boundaries and the number of freedom is reduced greatly through translating the inner unknown quantity to the boundary with basic solution.