| The landslide in songlincun,Bazhou is located in the low Middle Mountain hilly area of North Sichuan.In the rainy season of 2017,two slumps developed at the front edge.The survey found that the landslide is in the creep deformation stage,which has gradually intensified under long-term precipitation and other conditions.If the deformation continues to develop,the overall sliding will occur,which will cause serious damage to the personal and property safety of the local residents.Moreover,the landslide in the study area has It has a certain representativeness,and the relevant research can provide reference for similar landslides,and has a positive role in disaster prevention and mitigation.On the basis of mastering the research results of various kinds of landslides,this paper takes the landslide as the research object,through collecting and analyzing the existing regional geological,hydrological and meteorological data of the research site and surrounding areas,adopts the method of drilling + trench + geological mapping to carry out detailed investigation and geological analysis of the landslide area,and through collecting soil samples,rock samples and water samples to carry out relevant experimental research,to find out the landslide Physical properties of rock and soil engineering.Based on rhino software and griddle grid plug-in as the transition platform,the FLAC3 D simulation model of typical landslide section is established.Through the change of mechanical parameters of rock and soil layer and the application of external dynamics,the simulation is carried out under natural,rainstorm and earthquake conditions.The transfer coefficient method proposed in the code is used for quantitative calculation of stability under various conditions,and the typical section is checked with the help of limit equilibrium algorithm such as morgenstem pirce method of geo Studio software.Through these research processes and means,the main research results are as follows:The geological environment,scale structure,development characteristics,underground water occurrence and landslide disaster history of the landslide area are found out.The particle size analysis shows that the particle composition of gravelly soil and silty clay is obviously different.The overall engineering geological performance of the soil overlying the landslide is poor,and the underlying mudstone and sandstone bedrock have good mechanical stability.The test results provide data for stability evaluation Reference resources.Based on the comprehensive analysis and consideration of precipitation,lithology and mineral composition,topography and geomorphology,earthquake and water soil chemistry,the variation characteristics of strain,displacement and plastic area in different conditions are analyzed in FLAC3 D,which shows that these characteristics change more significantly under rainstorm,and the silty clay layer is the main soft deformation Zone,and the front soil body is the first to collapse The stability coefficient of 2-2 'typical profile is 0.858 ? 1.048,which is in an unstable or under stable state.Through the sensitivity calculation and analysis,the internal friction angle of soil has more obvious influence on the stability.The landslide in the study area is located in the area with weak structural control,and the rainfall gravity coupling plays an absolute leading role in this kind of soil landslide.The development process can be summarized as:development deformation,local tension crack collapse,creep sliding instability and other stages.Two schemes are designed under the combination of geological environment and engineering practice: one is the retaining wall outside the middle and rear highway of the landslide + front anti slide pile + rear edge fishpond seepage prevention + crack sealing;the other is the pile sheet wall outside the middle and rear highway of the landslide + rear edge fishpond seepage prevention + crack sealing.The two schemes are verified by FLAC3 D model and compared with each evaluation factor,and the second scheme is recommended. |
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