Study On Stability Evaluation And Control Engineering Measures Of Shuangbai Damaidi Landslide In Yunnan

Based on detailed data collection and field geological survey of the research area in Shuangbai Damaidi,Chuxiong,Yunnan,this paper comprehensively uses engineering surveying and mapping,drilling,shallow wells,trench exploration,indoor geotechnical tests,and numerical simulation.The lithology,geological structure,and hydrogeological conditions of the study area were investigated,and basic physical and mechanical parameters of the rock and soil bodies an d sliding zones in the study area were obtained.Qualitative analysis of Damaidi landslide using natural history anal ysis method;selection of transfer coefficient method for quantitative calculation of landslide stability;landslide 1-1 ',2-2',3-3 'based on numerical analysis software Midas GTS / NX 2D The stability of the profile was analyzed by numerical simulation.Based on the understanding of Damaidi landslide,a comparative analysis of three options for landslide management was conducted.Based on comprehensive analysis of the technical feasibility,economic rationality,and ease of construction of the plan,the optimal plan for landslide control is selected.The finite element numerical analysis software Midas GTS / NX is used to analyze the stabil ity of the landslide after treatment.The main research results obtained in this paper are as follows:1.The Damaidi landslide has been deformed and damaged since 1965.Later,due to earthquakes and rainfall,the original cracks in the early stage and the newly formed cracks in the later stage gradually expanded to the depth of the landslide body,and the rainwater infiltrated along the cracks.Relatively watertight,a relatively rich area of groundwater is formed above the fully strong weathering combinat ion zone.Under long-term immersion in water,the shear strength of the fully weathered layer decreases and the anti-sliding force decreases,gradually forming a shear slip surface.2.The qualitative analysis of the landslide using natural history analysis results are as follows: The landslide is in a unstable-basically stable state.The transfer coefficient method is used to quantitativel y calculate the stability of the landslide.The calculation results show that the landslide has a stability factor of 1.116 to 1.125 under natural conditions,which is an basic stable state;under a rainstorm condition,the stability factor is 1.005 To 1.026,it is understable.Under earthquake conditions,the stability coefficient is between 0.968 and 1.010,which is an unstable-unstable state.3.The finite element numerical analysis software Midas GTS / NX is used to analyze the stability of the landslide under natural conditions and rainfall conditions.The results show that the landslide is basically stable under natural conditions;the landslide is under-steady under rainfall conditions;the numerical analysis results are consistent with the calculation of the stable state of the landslide by the transfer coefficient method.4.According to the stability evaluation re sults of Damaidi landslide,three kinds of control measures are proposed for Damaidi landslide.Option one: cutting slope and reducing load + leading edge presser foot.Option two: Anti-sliding piles + interception,drainage ditch + ramming and filling of cracks.Option three: Anchor cable anti-sliding piles + interception,drainage ditch + tamping and filling cracks.The final choice is Option 2 to treat the landslide in Damai.5.Use numerical simulation software to simulate and analyze the treated landslide to verify the rationality of the reinforcement measures.Numerical simulation results show that after the treatment of the landslide in Damaidi,the stability factor of natural conditions is 1.253,and the landslide is stable.The landslide stability c oefficient of rainfall conditions is 1.157,which is a stable state.After treatment,the shear strain and displacement of the landslide were significantly reduced under natural conditions and rainfall conditions.The shear strain at the anti-slide pile at the front edge of the landslide body is small,and the shear strain zone is mainly distributed in the upper part of the landslide body.The above results show that the treatment effect of Damaidi landslide is good,and the selected treatment measures are r easonable to achieve the purpose of treatment.