Research On The Stability Of Expansive Soil Slope Of S-N Water Transfer Canal Under Overload

In this paper, the Handan-Xingtai slope, part of South-to-North Water DiversionProject, is studied. Researches are done on the engineering properties and slopestabilities. This paper introduces several aspects, including current research of theexpansive soil, characteristics and engineering properties. It also analyzes hazards ofexpansive soil slope on engineering buildings.Within the background of expansive and replacement soil slope, theoreticalcalculations, experimental studies and FLAC-SLOPE software simulation are usedrespectively to analyze its stability in overload and seepage conditions. Calculationsof expansive and replacement soil slope are divided into three conditions, namelywhen there is no water in the canal slope,1/3of design depth and1/3of increasedepth.In the theoretical part, limit equilibrium theories is used to analyze the stabilityof expansive soil slope under overload and no load conditions. Seepage and stabilityanalysis are done within the introduction of engineering characteristics, hydrologicaland geological conditions. After the statistical analysis, it derives the possible damagestatesand slide forms.In the experimental part, experimental model of expansive and replacement soilslope is created according to geometric similarity, the critical state instability similarconditions.In order to reach the limit equilibrium state, an external load is applied onthe canal slope crest, thus the morphology of canal slope can be examined. Throughperiments found, that there is a slow development process of expansive andreplacement soil slope from fracture development to significantly large deformationunder the situation of overload and water seepage. And large instable deformationareas of channel slope is occurred in the shallow layer of expansive soil slope.In the simulation part, the thesis introduced the characteristics, methods andapplication principles of FLAC-slope software. The stability of expansive andreplacement soil slope are simulated under three kinds of working conditions. Failuremodes of expansive and replacement soil slope can be seen through the simulationresults.Finally, with comprehensive analysis of theoretical calculation and softwaresimulation, it can be drawn that under the infection of overload and undergroundseepage, the most dangerous sliding surface of expansive and replacement soil slopeis compound curved form or single curved form. And it further verified byexperiments.