Study On The Sliding Mechanism Of Slag Accumulation Slope

At present,the gangue hills formed by the accumulation of slag are widely distributed in mine resource cities and occupy a large amount of land resource.With the enlargement of linear engineering construction scale such as roads and railways,slag slopes are formed due to the effect on the siting of linear engineering.This type of slope is dominated by overtop slope height and steep slope.The slope body is composed of loose coarse particles with low density.Geological hazards induced by human activity and rainfall are easily happened.This paper takes the K13-14 landslide of Nanhuan Road,Fuxin City as an example,adopting a combined method of field survey,field experiment,indoor experiment and numerical simulation to study the stress and strain characteristics of the slope body.Based on the above analysis,the sliding mechanism and influencing factors of this type of slope are studied and analyzed,and prevention advice is put forward.The following results have been achieved:?1?A plenty of information about nature,economy and human activities surrounding the landside area are acquired by conducting a comprehensive site survey of the landslide of K13-14 section of Nanhuan road in Fuxin.The engineering geological environmental conditions and basic features are determined by analyzing 6aspects of the study area such as topography and geomorphology,stratigraphic distribution,physical and mechanical properties of rock and soil,groundwater distribution,geological structure conditions and human engineering activities.?2?According to the characteristics of landslides obtained from field surveys and the data from drilling,inclinometer and surface displacement observation,we can get the information about the composition of landslide,the internal structure of slope,the distribution of landslide features and the deformation status of slope.There are 2 slip surfaces in the landslide based on the result of inclinometer observation and the limit equilibrium method.The area of landslide is partitioned based on the surface displacement observation results and the surface sliding characteristics.It makes the sliding deformation of the landslide can be described more effectively.?3?The natural density,the water content and the grading curve of the slope components are obtained through outdoor test.The grading curve for large-diameter triaxial test is simulated by equivalent substitution method through indoor screening test.The maximum dry density and the optimum water content are also determined by the curve and the these parameters of the samples for the test are also based on them.Triaxial shear test are performed to analyze the stress-strain characteristics,deformation characteristics and shear strength characteristics under different confining pressures.?4?A three-dimensional numerical model for the landslide of K13-14 section of Nanhuan road in Fuxin is established through a comprehensive use of software such as Autocad,Gocad,Surfer and Flac^3D.Numerical simulation analysis is carried out of the evolvement of slope deformation based on Flac^3D.To consider the slope deformation under two conditions:backfilling of earthwork at the top of slope and water infiltration.It is concluded that the backfilling of earthwork is the main reason for the landslide and the water infiltration accelerates the development of landslide.?5?A numerical model is built based on the main section of the landslide by using PFC^2D.The simulation process of slope deformation and failure considers the influence of backfilling and infiltration.The displacement of all steps are also monitored to get the real time information during sliding.To make a comparison with the calculation results of Flac^3D,the PFC^2D results also verify the reason of the slide and the distribution of slide surfaces.?6?Prevention suggestion are proposed to the landslide.Slope cutting and anti-slide pile are suggested to use in combination to prevent the slope from sliding again.Concreting and filling cracks and greening slopes are suggested to use to prevent water infiltration in slope body.