泸定6.8级地震公路地质灾害链效应分析

Analysis of the Chain Effect of Highway Geological Disasters in Luding M6.8 Earthquake

省道S217是2022年9月5日泸定6.8级地震中灾毁最为严重的公路,沿线灾害链生效应明显。通过实地踏勘,收集地质资料和前人研究成果,总结了公路沿线崩塌群、滑坡、泥石流次生地震地质灾害的分布规律及特征,并从灾害链的角度对地震诱发次生地质灾害进行剖析,归纳出地震—震裂山体—崩塌(滑坡)、地震—崩塌(滑坡)—堰塞湖—水流(冲刷)—泥石流、地震—滑坡—崩塌等灾害链模型,且通过对灾害链成灾机理和发展趋势的分析判断:部分灾害链已趋于稳定,但仍有部分灾害正在发展、或将形成隐患。为此,针对灾害链的孕灾环和激发环,建议通过监测、控制、消除激发环和改变新孕灾环的方式实现断链,提出了相应的断链措施,为灾后重建提供参考。

The provincial highway S217 is the most severely damaged highway in the“9.5”Luding M6.8 earthquake,and the chain effect of disasters along the line is obvious.Through field survey and collecting geological data and previous research results,the development and distribution laws and characteristics of secondary seismic geological disasters caused by collapses,landslides and debris flows along the highway are summarized,analyzes the secondary geological disasters induced by earthquakes are analyzed from the perspective of the disaster chain,and it is concluded accordingly as disaster chain models of earthquake-seismic cracking mountain-collapse(landslide),earthquake-collapse(landslide)-barrier lake-water flow(scouring)-debris flow,earthquake-landslide-collapse,etc.Based on the analysis of the disaster mechanism and development trend of the disaster chain,it is judged that some of the disaster chains have become stable,but there are still some disasters that are developing or will form hidden dangers.To this end,in view of the pregnant environment and the excitation condition of the disaster chain,it is suggested that the chain break be realized by monitoring,controlling,eliminating the triggering ring and changing the new disaster-producing ring,and the corresponding chain break measures are proposed to provide reference for post-disaster reconstruction.