Stability Analysis And Reinforcement Technology Of Soil Slope With Weak Interlayer Under Different Rainfall Conditions

As a kind of weak interlayer structure of lamellar or ribbon layer exists on the rock slope and rock soil slope,the anti sliding and anti overturning than smaller adjacent rock mass,especially under the condition of rain infiltration,due to the high permeability of soft interlayer,the rain infiltration rate of the inside of the slope to get to improve,to further reduce the stability of the slope,the formation of a serious threat to road safety.Therefore,this paper takes Hunan province Lichong Expressway(Beijing Zhuhai Expressway-Hunan Lin long slope sections)containing weak interlayer as the research object,first of all,according to the data of nearly 50 years of rainfall in Hunan province Changsha area,heavy rain,heavy rain and heavy rain to the three rainfall condition,and then using Geo-studio software to establish the finite element numerical bearing the slope soft interlayer model based on saturated unsaturated seepage theory,the seepage calculation of slope with weak interlayer characteristics,and then calculated the seepage characteristics of the slope into FLAC3D finite difference software,analysis of soft soil layer clamping stability,finally,select the most unfavorable rainfall conditions according to the simulation results of(rain)research on reinforcement slope with weak interlayer stability,provide theoretical support for engineering practice.The 3 important conclusions of this paper are as follows:(1)when the cumulative rainfall at 3 rainfall conditions caused by weak interlayer pore water pressure changing degree of order:Heavy rain>rainstorm>heavy rainstorm,in addition,due to the presence of weak interlayer,slope due to rainfall infiltration and landslides process in advance;3 kinds of rainfall conditions,slope surface the wetting front in the silty clay layer generally shows uniform infiltration,showing "V" shape distribution in the soft interlayer,when the rainfall,rainfall levels for the heavy rain in the wet front development rate is the fastest,followed by heavy rain storm,the slowest.(2)in the process of rainfall,sliding surface is first formed in the weak layer,and then extended toward the slope,the slope vertical settlement displacement increases,the rainfall stops,including slope stability of soft interlayer recovery has lagged behind.(3)under the most unfavorable rainfall conditions(heavy rain for a long time),the slope surface of the soft soil slope with weak interlayer shows a concave structure,and the stability is obviously improved.Therefore,the anchor bolt is used to support the weak interlayer road slope,the effect is obvious,and the scheme is reasonable.