爆破地震作用下结构的损伤及动力响应分析

针对建筑结构爆破地震响应研究中材料模型和结构模型过于简化的问题，采用已建立的岩石类材料的正交各向异性动力损伤本构模型，将其编制成动力有限元软件LS—DYNA的用户自定义子程序，模拟计算一个二层两跨典型砌体结构在不同爆破地震波作用下的动力响应．并分析了爆破地震波三要素对建筑结构的损伤及动力响应的影响，结果表明：地震波幅值的增加，可明显加剧结构的损伤，损伤可大幅增加结构应变响应；结构存在一个危险的频率段，并且这个频率段应在结构高阶振动模态对应的频率中；结构的损伤和动力响应还与震动波形有密切关系；当结构受迫震动阶段产生损伤时，爆破地震波持续时间对结构响应影响就很大。

Damage of Structures and Dynamic Response Analysis under the Action of Blasting Seism

According to the problem of oversimplification of material and structural models in researches of blasting seismic response of architectural structures,an existing orthotropic dynamic damage constitutive model was adopted to write users＇ self-defined subroutine of dynamic finite element software LS-DYNA with which the dynamic re- sponse of a two-storey,two-span and representative masonry structure were simulated under the action of different blasting seismic waves, and then, the influence of three main factors of blasting seismic waves on the damage of archi- tectural structures and dynamic response was analyzed. Results showed that the damage of structure would be great- ly enhanced with the increase of amplitude,increasing the strain response of structure remarkably. There exists a dangerous frequency section, which was in the frequencies corresponding to higher order vibration modal of structure. The damage and dynamic response of structure were significantly related with waveform,and if structure damaged during forced vibration phase, the duration time would influence dynamic response remarkably.