High Fill Embankment Slope Stability Analysis

Embankment is one of the main structure of highway subgrade, the stability and settlement of mountain high fill embankment has been focused on when considering the engineering problems. In the rainy southern mountain area, the embankment of highway in mountainous area will become saturated waterway embankment due to the influence of atmospheric rainfall and groundwater seepage, embankment soil will be gradually saturated and lead to the decrease of shear strength. If cannot be handled properly in a timely manner, embankment is extremely likely to have very large deformation or even fail.Based on Chongqing tea garden new town road high fill embankment slope engineering and monitoring of the actual situation, after it's completed,and through theory analysis, monitoring and numerical simulation analysis methods, the deformation characteristics of embankment slope during filling process and amplitude of groundwater level under the action of stress, deformation and slope stability are systematically studied, and the results were compared with the actual monitoring results. The main research work and results are as follows:(1) Filling process of slope embankment layer of Chongqing tea garden new town road is simulated with the finite method, deformation law of embankment during its filling is as follows: the maximum horizontal displacement is at the lower part of the slope in the location of the slope angle, and the emergence of "uplift" is at the slope toe front; the vertical settlement of the slope is at the top of slope; as the filling process, and the horizontal displacement of it increased first and then decreased, but overall the displacement is deviated from the filling soil; while the overall trend of vertical displacement increased gradually and the value of it was bigger when the vertical measuring point is closer to the crest of the slope.(2) After the brief introduction of the slope stability methods, the simplified Bishop method is adopted for analyzing the stability of Chongqing tea garden new town road embankment slope engineering, the most dangerous sliding surface and security factor were obtained an the influence of slope rate and slope height on the stability of slope were analyzed.(3) Based on the Chongqing tea garden new town high fill embankment slope, influences of no groundwater and groundwater level decline or rise of seepage field on the slope stability were analyzed. It is concluded that due to the decrease of groundwater level, the pore water discharge gradually and pore water pressure dissipate gradually and effective stress increase, the effect of matrix suction of unsaturated soil gradually strengthen, embankment slope stability coefficient increase gradually; due to the rising of groundwater level,water on the slope will soften soil, the role of buoyancy is enhanced and pore water pressure increased, all of what will decrease the stability of slope.(4) Based on in situ monitoring and numerical simulation after the embankment slope is completed, the slope displacement after embankment slope is completed is analyzed. After the embankment slope is completed, the slope displacement extension is most obvious at the initial stage, and as the time passed, the deformation increased, but not obvious, and has a trend of becoming stable.