关键词: 地震滑坡, Newmark滑动体位移模型, 蒙特卡罗随机模拟, 概率分析

Abstract: The 2004 Chuetsu earthquakes of Niigata (Japan) triggered numerous landslides, and the most widespread types of landslides were highly disrupted, relatively shallow slides and soil (debris) flows. To avoid and mitigate such seismic landslide hazard, this paper presents a method to evaluate the probability of slope failures using Newmark displacement on a pixel-by-pixel basis in a given area. The proposed method was able to integrate Newmark displacement modeling and Monte Carlo simulations with geographic information systems (GIS). In the modeling, an empirical attenuation relationship was utilized to calculate Arias intensity over this study area; and the variability of geotechnical parameters was taken into account to calculate coseismic displacement. After deriving the displacement from related inputs, the Monte Carlo simulations ran 1 000 times, and generated 1 000 displacement values for each grid cell; and then the displacement mean and standard deviation were calculated and its probabilistic distribution can be obtained. Finally, given 2 cm as a threshold value of displacement, estimated probabilities of displacement exceeding 2 cm were shown as a map of seismic landslide hazard. The resulting map was classified into four categories from very low to high level.

Key words: earthquake-induced landslide, Newmark displacement, probabilistic analysis, Monte Carlo simulations