Model test and numerical analysis of micropile-MSE wall
ZHANG Zhichao1,CHEN Yumin2
(1. Key Laboratory of Geohazard Prevention of Hilly Mountains,Ministry of Land and Resources of China,Fujian Geological Engineering Survey Institute,Fuzhou,Fujian 350002,China;2. College of Civil and Transportation Engineering,Hohai University,Nanjing,Jiangsu 210098,China)
Abstract:The micropile-mechanically stabilized earth(MSE) wall suitable for roadway construction in steep terrain of mountainous areas is a new type of earth retaining structure. To validate its working mechanism and effect,model tests and numerical simulation were conducted to study the multilevel surcharge induced static response of MSE walls on slope before and after the micropile reinforcement. The results indicate that the numerical method can simulate the model tests well. Under the surcharge loadings of 2–10 kPa,the measured subsidence of micropile-MSE wall is reduced by 11%–40% compared to that of unreinforced model,whereas the wall deflection is reduced by 50%–66%. The higher the surcharge loading,the larger the reduction is. The base and lateral earth pressures are also decreased notably. The inclined micropiles in the micropile-MSE wall play a more important role in the deformation control,which lead to a 25.9%–40.3% higher bending moment in the inclined piles than in the vertical piles under the surcharge loadings of 2–10 kPa. Therefore it is necessary to use the micropiles of higher strength as the inclined reinforcement in the MSE wall. Thus,the reliability of the micropile-MSE wall is verified preliminarily .
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