采用动力有限元方法,参照爆区现场的一实际三层砌体房屋结构,建立三维空间实体模型,并将底层的爆破地震波监测信号加载到砌体结构模型的基底,求解出有限元模拟的砌体结构其它各层的爆破振动响应值,并与监测结果进行了比较分析.对常见的2层～4层砌体结构房屋,各取一种典型结构在底部节点垂直方向上施加不同主频的爆破地震波进行动力有限元建模并模拟开裂过程,通过定义结构单元的临界失效状态来寻求典型砌体结构房屋的爆破振动安全标准值,并给出了2～4层典型砌体结构房屋在各主频段爆破地震波作用下的爆破振动安全标准.结果表明,现行的<爆破安全规程>中基于工程经验及宏观调查资料基础上制定出的爆破振动安全标准过于粗糙和笼统,对于同类建筑,没有考虑到结构个体的振动特性差异,并不能保证所有结构物的安全,不具有普适性.%A three-dimensional solid model was built for an actual three-storey masonry building in blasting filed.Measured signals of blasting seismic waves at the bottom were loaded onto the foundation base of the model, and blasting vibration responses of the other storeys calculated with dynamic finite element method were compared with the measured results. One typical structure was selected respectively among common masonry buildings of 2 ～4 storeys to build its finite element model, and blasting seismic waves of different dominant frequencies were loaded on its base nodes in vertical direction and the cracking course of the model was simulated. Safety standards of blasting vibration of typical masonry buildings of 2 ～4 storeys under blasting seismic waves of different dominant-frequency bands were given, they were obtained by defining critical failure state of structural element. The results indicated that the safety standards of blasting vibration in existing safety regulations for blasting made based on engineering experience and macro-survey data seem too gross and do not consider differences of vibration characteristics between structural individuals for one type of building;they can not be widely used because they can not guarantee the safety of all structures.
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