工程场地地震地裂灾害评价及其防治

Study on the seismic ground fracturing hazard and its prevention in engineering site

基于工程场地岩土体破裂的观点,采用理论解析、数值模拟和实验等手段,开展了西安场地未来50年内的地震地裂灾害评价及防裂抗裂研究。研究表明:未来50年内,场地中部地震地裂危险强于东西两端,城内地震地裂贯通、出露可能性大于城外。在满足基础安全深度的前提下,隐伏深度大于20m时,地面地震破裂危险较小;平行地裂段间距大于60m、左行雁列次级地裂段间距大于80m时,可考虑中间场地的使用;可利用波阻抗失配,采用柔性、刚性或刚柔结合等3种方案进行工程抗裂设计。

In the viewpoint of ground fracturing,this paper studied seismic ground fracture and its prevention in the coming fifty years in Xi'an.Using the method of theoretical analysis,numerical simulation and experiment,the paper drew some important conclusions as follows.In the coming fifty years,the risk of seismic ground fracturing in the middle part is greater than that in the east and west,in the city than outside the city. When safe depth of foundation is satisfied with requirements,and depth of buried fault is greater than 20 m,the seismic fracturing hazards on the ground surface is smaller.Then the middle yard can be used when the intervals of two paralle ground fissures and two leftlateral sense are bigger than 60 m and 80 m respectively. Taking advantage of mismatching of surge impedance,we can adopt the flexible project,rigid project,or their combination to design fracture resistance.