Study On Failure Mode And Stability Analysis Under Underground Excavation Of Bedding Rock Slope

In engineering construction,slope instability often endangers the national economy and people's safety.Therefore,the problem of slope stability has been concerned by engineering personnel.With the development of foundation engineering construction in China,it is inevitable to encounter the situation of underground tunnel crossing the slope.The underground excavation and unloading has deteriorated the existing environment of the slope and increased the risk of slope instability.Bedding rock slope is a kind of slope with a wide range of distribution.Bedding slip often occurs under the action of external disturbance,resulting in major geological disasters.Therefore,it is of great practical significance and practical value to study the stability of bedding rock slope under the condition of underground excavation.This paper analyzes the failure mode of bedding rock slope under the condition of underground excavation through similar model test and numerical simulation,and puts forward the corresponding stability calculation method based on the failure mode.Based on the similarity theory,considering the influence of rock slope inclination and excavation location on the failure mode of bedding rock slope,the similar model test of underground excavation of bedding rock slope is designed and completed.The displacement data of slope is sorted out and the regional displacement curve of slope is drawn.The discrete element calculation software UDEC was used to simulate and calculate the instability process of underground excavation of bedding rock slope,and the failure modes of bedding rock slope under the condition of underground excavation were determined to be collapse failure,cave-slip failure and slump failure.Considering the characteristics of progressive failure mode of the bedding rock slope,the stability of the bedding rock slope was analyzed for the first time with the structure of the fixed-end beam as the mechanical model,and the stability of the bedding rock slope was determined by calculating the collapse height of the rockmass above the excavation area and comparing it with the thickness of the overlying rock mass in the excavation area.On the basis of determining the potential sliding zone,the limit equilibrium method is introduced to calculate the sliding force and anti-sliding force of the potential sliding body and judge the stability of the potential sliding body.Finally,the software of slope stability calculation program of Visual Basic language is developed based on various calculation methods,which provides reference for engineers to analyze the stability of bedding rock slope under the condition of underground excavation.