A Model Test For The Stability Of Soft And Hard Interbedded Side-slope Induced By Rainfall

Generally speaking,the stability of bedding slope is poor,especially when engineering excavation exposes the level.It is more likely to happen poetry and rain under the action of rainfall.When a general project is located,it will take the initiative to avoid the bedding slope.However,in practical engineering practice,it is difficult to completely avoid it.The Syria railway is the key project in Sichuan Province,which goes through North montanic in Sichuan Province,and the Gulin railway station is an important node of the Syrian railway.It is an important transfer station connecting Xuyong to Gulin railway transportation.The stability of the slope of the station will directly affect the construction and operation of the railway.This paper is the basis of the investigation and research.A conceptual model is built for indoor test and numerical analysis,and the following research results are obtained:(1)When the excavation slope is divided,the deformation of the slope is weak,and its deformation occurs mainly in the strong elegance rock mass in the shallow surface of the slope excavation face.The surface generated by excavation provides space for slope deformation.In the continuous heavy rainfall condition,the fracture gradually passes through the top and bottom gradually,which is prone to become more and more weak and form sliding zone.Finally,the shear failure of the slope is caused.(2)When grading excavation slope,slope deformation occurs more obvious,which increases the total displacement of slope excavation progression and increases levels of excavation,slope deformation occurs mainly in slope excavation the upper part of the rock body deformation showing a slope descending from the surface to the inside,from the trailing edge of the forward edge of decreasing distribution,strongly weathered in the upper part of the slope of interbedded sandstone and mudstone interbedded with the weathered sandstone and mudstone junction,the most intense deformation,maximum up to 10 cm.After shearing rock dislocation occurred after the formation of cracks along the shear layer,these cracks in the rain and other conditions may gradually from top to bottom through the direct formation of slip bands,eventually slope shear failure.(3)The rainfall model test of the gently inclined,soft and hard interbedded slope is carried out by the debugged rainfall superposition sprinkler system and the model trough,and the high speed and ultra clear camera is used to make a regular snapshot of every side of the side slope,and the deformation of the broken table is recorded by the three-dimensional laser scanner in the rain gap,and the deformation and evolution process of the slope an with destruction mode are analyzed.(4)According to the data collected by four different sensors embedded in the slope,the relation between the change of the data and the change of the slope body is described in detail,and the response laws of water content and pore water pressure in different positions in the slope are summarized,and the non uniform cutting effect and fissure orientation of the cracks are obtained.Dynamic response rule and corresponding failure mechanism of slope under continuous heavy rainfall such as diversion effect and so on.(5)The three-dimensional discrete element software 3DEC is used to retrieve the deformation characteristics of the natural state of the gently inclined bedding soft and hard interbed slope,and the deformation characteristics and failure modes of the structural face under continuous strong rainfall,and compare with the laboratory results.The results show that the failure stage,the failure mode and the corresponding deformation characteristics obtained by the numerical calculation and analysis basically coincide with the corresponding deformation characteristics.Therefore,the numerical simulation basically reflects the whole process of the change of the physical simulation test.The two mutually corroborate the damage of the slope under the action of the dry and wet cycle of the continuous strong rain drop.Characteristics and instability mechanism.