摘要
由于地裂缝的存在破坏了场地的介质连续性，地震波在裂缝带的反射作用对场地的动力响应具有放大效应。以咸阳市某地裂缝为例，在研究地裂缝分布特征、活动规律的基础上，分析确定了该区地裂缝的成因类型，并通过数值模拟研究随机地震荷载作用下地裂缝场地的动力响应，确定了该地裂缝场地的动力响应特征，以及上盘60 m至下盘30 m放大效应显著的范围。结合现有地裂缝勘查规范确定了咸阳市地裂缝的避让距离原则：在土地宽裕的情况下，应按照规范的要求进行避让；在城市用地紧张的情况下，一类建筑物上盘33 m，下盘18 m，二类建筑物上盘22 m，下盘14 m，三类建筑物上盘8 m，下盘6 m；在强震作用下，由于地裂缝带的地震放大效应，建议适当放大避让距离，可考虑取上盘60 m，下盘30 m。
Abstract
Due to the destruction of existed cracks to the continuity of site medium,reflection of seismic wave in fracture zone has amplification effect on the dynamic response of the site.A case study is done to a ground fis-sure in Xianyang,Shaanxi.Based on distribution characteristic and activity rule of the ground fissure,its genetic types are determined.Dynamic response of the ground fissure under random earthquake loading is numerical simu-lation,which fixed its dynamic response characteristics and the range of obvious amplification effect in upper 60 m to lower 30 m.Avoidance distance principles are determined according to the existing specification of ground fissure exploration.The avoidance distance should be in accordance with the specification requirements when land is suffi-cient.When land is limited,distances of the hanging wall and the footwall of One Class,Two Class and Three Class buildings are,33 m and 18 m,22 m and 14 m,8 m and 6 m,respectively.Considering amplification effect of fracture zone in great earthquakes,avoidance distances are suggested to be appropriately enlarged as 60m and 30 m for instance for the hanging wall and the footwall.
基金项目
国家自然科学基金(40972181)
国家自然科学基金(41302251)
陕西省自然科学基金(2013JQ5005)
长安大学中央高校基金(2013G3262011)
陕西省咸阳市防震减灾,“十一五,“重点项目之一”咸阳市地震小区划项目,“()
国家科技期刊平台
NSTL
维普
万方数据