Analysis And Assessment Of Rock Slope Stability In Qingshui To Guanmen Road

In recent years,a large number of mountain railways and highways are constructed in the domestic.Because the terrain is strategically situated and difficult of access,it prone to collapse and falling rocks,which would bring casualties and damage to the country and the people.In this paper,the typical collapse along Qingshui to Guanmen reconstructed road was studied to provide the basis and reference data for the prevention and treatment of slope failure by researching and evaluating the stability of the collapse systematically.Through analyzing topography,meteorology and hydrology,hydrogeology,formation litho logy,geological structure and regional stability as well as human activities in the study area and combining the on-site survey data and the basic characteristics of the slope,the failure modes and mechanisms were confirmed,and the failure mode that may occur come to be sliding.In this paper,the qualitative and quantitative evaluation methods were both used to analyze the stability of the slope.For the qualitative evaluation method,the stereographic projection method was used,and its result indicated that,cut by the structure surface,the rock mess was in a less stable state,because it has formed to be a wedge.Especially under the action of rain water and earthquakes,collapse and rockfall would occur very likely.For the quantitative evaluation method,the limit equilibrium method and numerical simulation method were used.There are two limit equilibrium methods are used in this paper,which are the unbalanced thrust method and SARMA method.The two-dimensional discrete element software UDEC was applied as a numerical simulation method to model and simulate.There are three calculation conditions,which are natural condition,heavy rain condition and seismic condition.According to the results,under the natural condition,the safety factors from limit equilibrium method and numerical simulation were greater than 1.25,which indicated that the slope is stable in the natural condition.Under the heavy rain condition,the safety factors from the limit equilibrium method and numerical simulation method were both reduced,which indicated that in the case of rainwater infiltration,the stability of the slope has decreased.Under the earthquake condition,the Sine wave input from the bottom was used to simulate seismic waves.Affected by dynamical response,stability of the rock mess reduced.The safety factor of each method was less than 1,which indicated that under the earthquake condition,it would highly likely occur that the slope would lose stability.Because under external force,dangerous rock mass on the east side of Dazhuang Village prone to collapse and rolling stones,in this paper,the two-dimensional simulation software Rockfall was used to predict the rockfall trajectory.The calculation results consisted of speed of the rolling stones,drop height,jumping height and energy,providing a theoretical basis for the collapse prevention project design.At last,based on the damage that the unstable slope hazards in the region may cause and its geological conditions,a comprehensive improvement program is suggested that taking measures combining active defense and passive block based,with removing localized unstable rock and establishing warning labels.