ISSN 1000-3665 CN 11-2202/P

    舟曲江顶崖滑坡的早期判识及风险评估研究

    A study of the early identification and risk assessment of the Jiangdingya landslide in Zhouqu county

    • 摘要: 如何提前判识滑坡变形并对其进行早期风险评估已成为地质灾害防治领域的研究热点。文章以舟曲白龙江流域江顶崖堆积层滑坡为反分析案例,进行了滑坡变形早期判识及风险评估综合研究,提出了小基线集雷达干涉(SBAS-InSAR)技术解译分析、地质-力学联合分析、动力过程数值模拟分析三者相结合的滑坡变形早期判识与风险评估全流程分析模式。基于SBAS-InSAR技术解译能够准确地判识江顶崖滑坡的分布范围及早期形变特征,江顶崖滑坡的变形破坏模式为牵引式,滑坡体长度约680 m,宽度约210 m。基于早期识别信息,地质-力学联合分析表明:江顶崖滑坡为典型的老堆积层滑坡,前缘局部变形,破坏模式为牵引式,滑坡体平均厚度约35 m,滑床整体坡度较缓,失稳后运移速度不大。选取符合江顶崖滑坡体滑移摩擦特征的库伦摩擦模型,基于深度积分连续介质方程,分析计算滑坡体的动力学过程,结果表明:滑坡体滑移速度不大,最大值约为2.2 m/s,运动方式表现为推挤白龙江河道,堵江可能性较小,并且江顶崖滑坡体前缘错动完成后,该滑坡体滑移速度从前缘到后缘快速降为0,表现为牵引式运动特征。本次分析结果与实际相符,吻合度较高,采取的综合分析方法及研究模式可用于舟曲白龙江沿岸类似滑坡的早期判识及风险评估。

       

      Abstract: How to identify deformed landslides in advance and conduct early risk assessments on them has become a research hotspot in the field of geological disaster prevention and control. In response to the above problems, the Jiangdingya landslide in the Bailong River Basin in Zhouqu is taken as a back analysis case, and a comprehensive study of the early identification and risk assessment of the landslide is carried out. In this paper, a full-process analysis method is proposed, which combine the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technology interpretation, geo-mechanical analysis and dynamic process simulation. The research results show that the SABS-InSAR technology interpretation can effectively identify the range of the Jiangdingya landslide and its early deformation. It may be preliminarily determined that the failure mode of the Jiangdingya landslide is trailed and the plane characteristics of the landslide body is generally about 680 m in length and 210 m in width. Based on the early identification information and through geo-mechanical analysis, it is finally identified that the instability problem of the Jiangdingya landslide is a typical deformation problem of the front edge of the old accumulation layer landslide. The failure mode is the traction slip failure, the average thickness of the landslide body is in about 35 m, the overall slope of the sliding bed is relatively slow, and the moving speed is not large after instability. On the basis of the above analyses, a Coulomb friction model that conformed to the sliding friction characteristics of the Jiangdingya landslide body is selected. Based on the depth integral continuum equation, the dynamic process of the Jiangdingya landslide body is calculated and the speed of the landslide body is monitored. In terms of velocity monitoring curves and accumulation pattern, the sliding velocity of the landslide body is not large, the maximum value is about 2.2 m/s, the overall performance is pushing the Bailong River channel, and the possibility of blocking the river is relatively small. In addition, when the displacement of the front edge of the Jiangdingya landslide body is completed, the speed of the landslide body from the front edge to the rear edge quickly drope to zero, and the movement process is characterized by the traction movement. The analysis results of the Jiangdingya landslide in this paper are consistent with the actual event of the Jiangdingya landslide. The comprehensive analysis method and research model can provide a good reference for the early identification and risk assessment of similar landslides in the Bailong River Basin in Zhouqu county.

       

    /

    返回文章
    返回