地下工程数值计算中地震动输入方法选择及实现

CHOICE AND IMPLEMENTATION OF SEISMIC WAVE INPUT METHOD IN NUMERICAL CALCULATION FOR UNDERGROUND ENGINEERING

在运用有限元数值方法进行地下结构抗震分析中,人工边界及地震动输入方法将直接影响到计算精度。在分析人工边界原理及常用地震动输入方法的基础上,研究地震动输入方法与人工边界间的相互作用。研究结果表明,不同地震输入方法将显著影响人工边界的吸收性能,而不同的人工边界需要采用与其相适应的地震动输入方法。接着分析两者相互作用的机制,并以无限元人工边界为例提出与其相适应的地震动输入方法,并编制相关输入程序,实例计算结果表明,所提出的地震动输入方法及相应的输入程序具有良好的精度。研究内容可为地下结构有限元抗震计算中人工边界及地震动输入方法的选择提供依据。

Artificial boundary and seismic input method directly affect the calculation accuracy in aseismic analysis of underground structure using finite element method（FEM）. The interaction between artificial boundary and seismic input method is studied on the basis of principle of artificial and seismic input method. The results show that different input methods significantly affect the efficiency of artificial boundary; and different artificial boundaries need compatible seismic input methods. The seismic input method compatible with artificial boundary and input program are proposed. The results using this input method and input program are in good agreement with theoretical solutions. Thereby, the theoretical basis of artificial boundary and seismic input method is provided for underground structures in seismic analysis using FEM.