基于不同位移预测模型的地震滑坡危险性评估研究-以天水地区为例

近年来,Newmark累积位移分析方法经过不断的改进和应用成为国际主流的地震滑坡危险性评估方法之一,众多学者基于位移预测模型开展区域地震滑坡危险性评估,然而鲜有针对不同位移模型对评估结果影响的定量研究。以天水地区为例,基于不同的位移预测模型开展地震滑坡危险性评估,对比位移模型对地震滑坡危险性评估的影响,探讨建立适用于我国的Newmark位移预测模型。结果表明:基于不同位移预测模型评估所得的地震滑坡危险性结果整体趋势一致,均能区分区域地震滑坡危险性等级的相对差异,但在同样的危险性分级标准下,所得中、高危险区的分布范围有较大差异。这与位移模型的函数形式及其区域相关性有关,在引入Newmark累积位移分析方法开展地震滑坡危险性评估的同时,应尽快建立考虑地震动衰减特征和工程地质背景的Newmark位移预测模型,为中国潜在地震滑坡危险性预测评估、震后滑坡快速评估等提供技术支撑。

THE INFLUENCE OF DIFFERENT NEWMARK DISPLACEMENT MODELS ON SEISMIC LANDSLIDE HAZARD ASSESSMENT: A CASE STUDY OF TIANSHUI AREA, CHINA

Recent years, the Newmark sliding-block model is one of the most wildly-used methods for assessing the stability of slopes during earthquakes; however, the influence of different Newmark displacement models on seismic landslide hazard assessments need to be investigated and quantified. Through the comparison between the displacements estimated by various Newmark displacement models in the Tianshui area, the influence of Newmark displacement models on seismic landslide hazard assessments are discussed. The results show that the overall tendency of the seismic landslide risk assessment based on different displacement prediction models is consistent; however, due to the region dependent and various function forms of these models, there is a great difference in the distribution of moderate and high seismic landslide hazard area. It suggests that a Newmark displacement prediction model considering the attenuation characteristics of ground motion and the engineering geological background of China should be established as soon as possible, which will provide support for the potential seismic landslide hazard assessment and the rapid assessment of post-earthquake landslide.