本文通过天水市北山野外调查和室内分析相结合的方法,开展基于Newmark累积位移法的地震黄土滑坡危险性分析.分析了研究区的孕灾背景,结合现有滑坡和不稳定斜坡的调查数据,在充分考虑了震源方位角和斜坡坡向角的角度关系基础上,对优势坡向角和劣势坡向角下的斜坡易发性进行分析计算,然后用回归方程求出PGA为0.3 g时斜坡的累积位移,最后计算出斜坡在地震荷载下的失稳概率.在此基础上,对北山进行地震黄土滑坡的危险性评价.分析结果表明:在Newmark模型的地震黄土滑坡危险性评估中引入斜坡坡向角和震源方位角关系,有利于提高小区域(大比例尺)风险评估的准确性.%Based on the method of field investigation and indoor analysis of Beishan in Tianshui City, Gansu Procince, the analysis of the hazard analysis of the seismic loess landslide is carried out in this article based on the Newmark accumulated displacement method. Through analyzing the disaster-forming environment, combining with the investigation data of the existing landslides and unstable slopes, in fully consideration of the angle relationship between the azimuth angle of the source and the slope angle of the area, the calculation and comparison of the slope prone angle under the dominant slope angle and the inferior slope angle are carried out. Then the accumulation of slope displacementis calculateby using the regression equation when the PGA is 0. 3g. Finally, the probability of instability of slope under earthquake load is calculated. On this basis, the risk assessment of the Seismic loess landslide of Beishan area was carried out. The analysis results show that introducing the relationship between the slope angle and the azimuth of seismic source in the risk assessment of the Loess Landslide in the Newmark model is helpful to improve the accuracy of the risk assessment of the small area ( large scale) .
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