【摘要】 利用汶川地震获得的强震记录及诱发的大量崩滑数据,对地震触发滑坡和Arias强度的关系进行了研究,得到汶川地震在龙门山震区Arias强度可以触发崩滑的水平向下限值约为0.4m/s,上限值可以定为4m/s,研究区不同出露地层可以触发崩滑的Arias强度变化范围不同,平均下限不超过1.0m/s.对部署于龙门山断裂带的强震数据拟合,得到汶川地震龙门山震区Arias强度的衰减关系.利用衰减关系对地震触发崩滑影响区域的估计与实际情况比较吻合,表明综合了地震动记录的振幅、持时和频率信息的Arias强度参数与地震地表破坏程度关系更为密切.可以将Arias强度参数应用于震后地震触发崩滑等地质灾害影响区域的评估工作,评估结果较以烈度作为评估因子的结果更为集中,比较适合于震后应急期间灾害快速评估,可为应急救援决策和方案的制定提供参考信息.更多还原

【Abstract】 Based on the data obtained from the Wenchuan Earthquake,the relationship between earthquake-induced landslides and Arias intensity(I_a) was studied.The results included:the threshold of I_a was about 0.4m/s,and 4m/s could be regarded as the upper limit.Different stratum with different I_a variation scope,the average I_a was about 1.0m/s in the Longmenshan earthquake-hit areas.I_a attenuation law was established based on the strong motion records distributed long the Longmenshan Faults.The estimated result from this attenuation was fit well with real case,which showed I_a paramter that mixed the information of amplitude,duration and frequency was more relevant with earthquake surface damages.The area evaluated from Arias attenuation was more concentrated than that of earthquake intensity.Therefore,Arias intensity can be used to quickly estimate affected area of earthquake-induced landslides to provide information for decision making and hazard evaluation during earthquake emergency rescue time.更多还原