浙江省文泰震区地震滑坡危险性评估

地震滑坡灾害的震前预测与震后快速评估已成为减轻地震次生灾害的重要手段之一。本文使用简化Newmark模型,设定地震震级(M_S5.0),利用区域地质图、数字高程模型等基础数据,考虑地形对地震动的放大效应,对文泰震区潜在同震滑坡区域开展评估工作。研究表明,干燥与饱和状态下,设定地震作用下研究区内地震滑坡高危险区均主要分布在距设定震中15km以内的范围内,其分布与区内岩土体处于临界稳定状态的分布趋势相同。区内水库坝址与水库库体未受到潜在同震滑坡的影响,划定的重点关注区内位于潜在滑坡体下方的千秋门村、驮加村、高西村、杜山村、南峤村、包坑村、龙前村、新厂村以及各级公路易受到同震滑坡的影响,应提升重点关注区内承灾体的风险防范能力,尽可能减少潜在同震滑坡对区内生命财产安全造成的威胁。

Risk Assessment of Earthquake-Triggered Landslides in the Wentai Earthquake Zone, Zhejiang Province

Pre-earthquake prediction and rapid post-earthquake assessment of earthquake-triggered landslide hazards have become one of the important ways for mitigating secondary seismic hazards. In this paper,we use a simplified Newmark model to predict the potential earthquake-triggered landslide areas in the Wentai earthquake zone by setting the earthquake(M_S5.0),using basic data such as regional geological maps and DEM,with the consideration of the amplification effect of topography on ground shaking. The study shows that under both dry and saturated environments,the high-risk areas for earthquake-triggered landslides in the study area are mainly located within 15km of the set epicentre,and their distribution is the same as the distribution of rock-soil mass in the area in a critical stable state. The reservoir dam site and reservoir body in the area are not affected by potential earthquake-triggered landslides,while the villages of Qianqiumen,Tuojia,Gaoxi,Dushan,Nanxiang,Baokeng,Longqian and Xinchang,as well as roads at all classes in the focus area,are vulnerable to earthquake-triggered landslides. The risk preparedness capabilities of disaster-bearing bodies in the focus area should be enhanced to minimise the threat to life and property in the area caused by potential earthquake-triggered landslides.