摘要
落井沟位于四川省泸定县得妥镇东南部,从沟口至其东南部约11 km处有正在运营的大岗山水电站。为有效防止落井沟泥石流对得妥人民的生命财产及大岗山水电站的运维造成的威胁与损毁,开展对泸定震后落井沟内物源分布特征与不同降雨周期下泥石流运动演化过程分析。“9·5”泸定地震后,耦合现场调查与地震前后遥感影像解译,得出强震致使落井沟流域内产生滑坡37处,总面积约0.125 km^(2),并采用LiDAR航拍技术优化解译结果,得到实际松散堆积物方量为15.52万m^(3)。随后结合精准物源、精细化地形及5%、2%、1%降雨频率,开展基于OpenLISEM数值计算的落井沟泥石流运动演化特征研究。结果表明:5%、2%、1%降雨重现周期下落井沟泥石流运动过程的最大泥深分别为6、8、11 m,最大流速分别为5、7、10 m/s;5%、2%降雨频率下泥石流对大渡河的堵江程度较小,1%频率下可造成半堵江状态。
Luojing Gully is located southeast of Detuo Town,Luding County,Sichuan Province,and approximately 11 km from the gully opening to its southeast is the Dagangshan hydropower station.To effectively prevent the threat and damage caused by debris flow in Luojing Gully to the operation and maintenance of the Dagangshan hydropower station,the distribution characteristics of the materials in Luojing Gully after the“9·5”Luding earthquake and the motion evolution process of debris flow under different rainfall cycles were analyzed.From on-site survey and remote sensing image interpretation of LiDAR aerial photography before and after the Luding earthquake,it was concluded that 37 landslides with a total area of about 0.125 km^(2) took place in Luojing Gully,and the actual amount of loose deposits was 155200 m^(3).Thus,combined with precise material source,refined terrain,and 5%,2%,and 1%rainfall frequencies,OpenLISEM numerical calculation was performed to characterize the motion evolution of the debris flow in Luojing Gully.The results revealed that during the recurrence periods of 5%,2%,and 1%rainfall,the maximum mud depths and maximum flow velocities are 6,8,and 11 m and 5,7,and 10 m/s,respectively.At 5%and 2%rainfall frequencies,debris flow has a small blocking degree to the Dadu River,and at 1%frequency,it can cause a half blocking state.
作者
李林泽
常鸣
李宏杰
胡锦凤
徐恒志
刘沛源
LI Linze;CHANG Ming;LI Hongjie;HU Jinfeng;XU Hengzhi;LIU Peiyuan(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,Sichuan,China;Shandong Zhengyuan Digital City Construction Co.,Ltd.,Yantai 264670,Shandong,China)
出处
《地震工程学报》
CSCD
北大核心
2023年第5期1116-1124,共9页
China Earthquake Engineering Journal
基金
国家自然科学基金(42077245)
第二次青藏高原综合科学考察研究(2019QZKK0902)。
关键词
泸定地震
落井沟泥石流
灾变预测
运动演化
Luding earthquake
debris flow in Luojing Gully
catastrophe prediction
motion evolution
