台风暴雨诱发大型凝灰岩滑坡形成机理与动力学特征OA
Mechanism and dynamics of large-scale tuff landslides triggered by typhoon-induced rainstorms
近年来,我国东南沿海由台风暴雨诱发的大型凝灰岩滑坡频繁发生,造成严重的人员伤亡和财产损失.2019年8月8日,台风"利奇马"引发的暴雨诱发了浙江省永嘉县山早滑坡,导致32人死亡,该事件是近年来浙江省人员伤亡最为严重的地质灾害事件之一.以山早滑坡为例,开展了台风暴雨诱发的大型凝灰岩滑坡的形成机理和动力学特征研究.首先基于山早滑坡的地质环境条件和基本特征,分析了其形成机理,随后利用颗粒流程序(Particle Flow Code,PFC)离散元数值模拟方法,再现了山早滑坡的动力学过程.结果表明:①该滑坡的形成机理是降雨通过后缘裂缝优势入渗,使后缘裂缝中地下水水位上升,进而对坡体施加了向外的水平推力和渗透压力,增大了坡体的下滑力;同时,凝灰岩中的泥质夹层受到浸泡后,其剪切强度降低,从而形成了滑带,减小了坡体的抗滑力.②该滑坡具有明显的高位滑坡特征,失稳后滑体突然启动并急剧加速,其速度在短时间内达到10 m/s以上,并完全堵塞了山早溪;滑体与地面剧烈碰撞发生动力破碎而碎屑化;前缘滑体速度急剧减小,并在攀爬河谷对面岸坡的过程中逐步停止运动,中部滑体推挤前部急剧减速的滑体、后部滑体推挤、前部滑体向前运动,动能从后部滑体传递至前部滑体;最终,大部分中部滑体超覆前部滑体,后部滑体超覆中前部滑体,因此,后部滑体的运动距离反而最长,中部滑体次之,前部滑体的运动距离最短.研究结果可为东南沿海地区台风暴雨诱发大型凝灰岩滑坡的早期识别、风险评估和防治工程设计提供理论支撑.
In recent years,large-scale tuff landslides triggered by typhoon rainstorms have frequently occurred in southeastern China,causing severe casualties and property damage.On August 8,2019,the Lizhima typhoon-induced Shanzao landslide in Yongjia County,Zhejiang Province,resulted in 32 deaths,making it one of the most catastrophic geological disasters in Zhejiang in recent years.This study takes Shanzao landslide as an example to investigate the mechanism and dynamics of large-scale tuff landslides induced by typhoon rainstorms.We analyze the mechanisms of Shanzao landslide based on its geological conditions and basic characteristics.It is concluded that preferential infiltration of rainfall through rear fractures is a key triggering factor,as rising water levels in these fractures exert outward horizontal thrust and seepage pressure,increasing the driving force of the slope.Additionally,the clay interlayers in the tuff become weakened due to saturation,leading to reduced shear strength and the formation of a slip zone,thereby diminishing the resistance of the slope.We also reproduce the dynamic process of Shanzao landslide using the PFC discrete element numerical method.The results indicate that the landslide exhibits clear characteristics of a high-position failure.After failure,the slide mass initiates abruptly and accelerated sharply,reaching speeds over 10 m/s in a short time,completely blocking Shanzao Creek.The slide mass undergoes dynamic fragmentation and debris flow upon violent impact with the slope foot.The front part decelerates rapidly and gradually stops while climbing the opposite valley slope.The middle section is pushed forward by the rear section,transferring kinetic energy from the rear to the front.Ultimately,most of the middle section overrides the front,and the rear section overrides the middle,resulting in the longest travel distance for the rear section,followed by the middle,and the shortest for the front.The findings provide theoretical support for early identification,risk assessment and prevention project design of large tuff landslides induced by typhoon rainstorms in southeastern coastal areas.
王紫剑;张明;李贵仁;平措朗加;刘大金;张昭辉;王虎;吴友银
自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||华北有色工程勘察院有限公司,河北 石家庄 050021自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||中国地质大学(武汉)工程学院,湖北 武汉 430074自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||华北有色工程勘察院有限公司,河北 石家庄 050021西藏自治区地质矿产勘查开发局第五地质大队,青海 格尔木 816000自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||华北有色工程勘察院有限公司,河北 石家庄 050021||中国地质大学(武汉)工程学院,湖北 武汉 430074自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||华北有色工程勘察院有限公司,河北 石家庄 050021自然资源部金属矿山地下水灾害防治工程技术创新中心,河北 石家庄 050021||华北有色工程勘察院有限公司,河北 石家庄 050021中国地质大学(武汉)工程学院,湖北 武汉 430074
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台风暴雨大型凝灰岩滑坡失稳机理动力学特征数值模拟山早滑坡
typhoon-induced rainstormlarge-scale tuff landslidefailure mechanismdynamics characteristicnumerical simulationShanzao landslide
《安全与环境工程》 2026 (1)
19-29,11
国家自然科学基金面上项目(41772334)华北有色工程勘察院有限公司重点科技攻关项目(CXZX-HZ-2023-01)
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