供水工程民和组地层区斜坡深层变形破坏模式分析

Analysis of Deep Deformation and Failure Modes of Slopes in the Minhe Formation Strata of Water Supply Engineering

目的红层软岩斜坡深层变形破坏具有一定隐蔽性,为解决寻找和识别具有一定隐蔽性的民和组地层区斜坡深层变形破坏变形体的问题。方法结合引黄济宁供水工程,依据民和组地层区斜坡变形破坏现象的调查分析,寻找已有深层破坏形成的滑坡体,反分析滑坡体破坏前原始斜坡模型,模拟分析原始斜坡滑动破坏触发因素,建立民和组地层区典型斜坡深层变形破坏模式;然后根据建立的斜坡深层变形破坏模式,寻找识别民和组地层区深层变形破坏斜坡变形体,对典型斜坡变形体构建三维数值模拟模型,分析天然、地震及降雨等条件下的斜坡变形体的稳定性。结果通过研究,建立了民和组地层区不同岩段典型斜坡深层变形破坏模式,识别出民和组地层区供水工程22#支线沿线有一个大型深层变形破坏斜坡变形体,在暴雨条件下会沿砾岩层与泥岩夹层交接面发生深层滑动破坏。结论通过建立典型斜坡深层变形破坏模式识别深层变形破坏斜坡变形体并分析其工程稳定性,可以减少意外发生斜坡深层变形破坏现象,研究成果可为工程施工图设计提供依据,也为民和组地层区地质灾害分析提供参考。

Objective To solve the problem of searching and identifying the deformation bodies of deep deformation and failure of slopes in the Minhe formation stratigraphic area with a certain degree of concealment since the deep deformation and failure of red soft rock slopes have a certain degree of concealment.Methods With the Yellow River Diversion to Xining Water Supply Project as the object of study and based on the investigation and analysis of slopes deformation and failure phenomena in the Minhe formation stratigraphic area,the authors searched for landslide bodies that had already formed deep damages,analyzed the original slope model before the landslide body failure,simulated and analyzed the triggering factors of original slope sliding failure,and established a typical deep deformation and failure mode of slopes in the Minhe formation stratigraphic area.Then,based on the established deep deformation and failure mode of the slope,the research identified the deformation bodies of the deep deformation and failure slopes in the Minhe formation stratigraphic area,constructed a three-dimensional numerical simulation model for typical slope deformation bodies,and analyzed the stability of slope deformation bodies under natural,seismic,and rainfall conditions.Results Through the study,the deep deformation and failure modes of typical slopes in different rock sections of the Minhe formation stratigraphic area were established,and a large deformation and failure slope deformation body was identified along the 22#branch line of the water supply project in the Minhe formation stratigraphic area.Under the condition of rainstorm,deep sliding failure would occur along the interface between gravel and mudstone interlayer.Conclusion By establishing typical deep deformation and failure modes of slopes,identifying the deformation bodies of deep deformation and failure slopes and analyzing their engineering stability,it is possible to reduce the occurrence of unexpected deep deformation and failure phenomena of slopes.The research results provides a basis for engineering construction drawing design and reference for geological hazard analysis in the Minhe formation.