【摘要】 黄河黑山峡大柳树坝址区存在大面积、大范围的岩体松动现象,主要特征是岩体应力释放,结构面张开,密度显著下降。为进一步研究岩体松动的成因机制,在详细地调查区域地质背景条件及区域地震动力作用基础上,提出了地震动力作用与岩体松动现象的内在联系,通过三维有限元数值模拟计算,进一步证明了大柳树坝址区存在的大范围岩体松动与历史上该地区发生的强烈地震具有密切关系。因此,在目前的工程地质条件下,一旦发生同样规模的地震活动,坝址区所遭受的破坏程度会更大。更多还原

【Abstract】 The phenomenon of large-area dynamic relaxation of surrounding rockmass has been observed in Daliushu dam site area of the Yellow River, which is characterized mainly by release of geostatic stresses, open of structural planes and marked reduction of density of rocks. In order to study the genetic mechanism of this rockmass relaxation, the intrinsic relationship between dynamic effect of earthquaken and relaxation is put forward in this paper on the basis of detailed investigations of regional geological environments and regional seismic dynamics and in addition 3-D FEM numerical simulations are conducted on the relaxation phyenomenon. The computing results have shown that the large-area rockmass relaxation in Daliushu project site is closely related to the intensive seimic history. Consequently, the dam site will be damaged more seriously once the seismic activity of the same scale happens.更多还原