玉溪市地震诱发滑坡危险性分析

Earthquake-induced landslide hazard analysis in Yuxi City

针对位于高地震烈度区域的云南省玉溪市开展了地震诱发滑坡危险性分析。分析中考虑不同岩土体含水状态对地震滑坡危险性的影响,采用Newmark位移预测模型计算饱和和干燥状态下区域累积位移,并以此判别区域地震滑坡危险等级。分析得出以下结论:玉溪市临界加速度值大部分大于0.98 m/s^(2),不同岩土体含水率对临界加速度计算结果影响较为显著;岩土体饱和状态下低危险区域面积达到92.6%,绝大部分区域在地震作用下发生诱发滑坡的危险性较小;高、极高危险区面积会随着岩土体内孔隙水含量的增加而扩大;新平彝族傣族自治县的高、极高危险区的分布为全市最多,且主要聚集在老厂乡、桂山、古城、新化乡等乡镇街道。该研究结果为玉溪市的防震减灾资源配置提供了依据。

This paper carried out the earthquake-induced landslide hazard analysis in Yuxi City, Yunnan Province, China. The impact of different water contents of rock and soil layers on the landslide hazard is taken into account, and the Newmark displacement prediction model is employed to calculate the regional cumulative displacements in the saturated and dry states respectively to determine the regional landslide hazard levels. The conclusions are drawn as follows: most of the critical acceleration values in Yuxi City are greater than 0.98m/s^(2), and the different water content of rock and soil mass has a significant impact on the calculation results of critical acceleration;the area of the low-hazard area under the saturated state reaches 92.6%, indicating that the risk of earthquake-induced landslide is relatively low in most areas;the high and extremely high hazard areas expand with the increase of pore water content, so it is necessary to strengthen prevention and take appropriate measures in the rainy season;the high and extremely high hazard areas are mostly located in Xinping Yi and Dai Autonomous County, most of which are concentrated in Laochang, Guishan, Gucheng, and Xinhua townships.The research results provide a basis for the allocation of earthquake prevention and disaster reduction resources in Yuxi City.