CONSOLIDATION ANALYSIS OF STONE COLUMN-REINFORCED COMPOSITE GROUND BASED ON TWO-DIMENSIONAL ELASTIC DEFORMATION
LU Mengmeng1，2，XIE Kanghe3，ZHOU Guoqing1，2，LI Ying3
(1. State Key Laboratory for Geomechanics and Deep Underground Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221008，China；2. School of Mechanics and Civil Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221008，China；3. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China)
Abstract：Firstly，the two-dimensional elastic deformation behaviour of composite ground under the influence of excess pore water pressure is analyzed. Analytical solutions are obtained for the volumetric strain，stress and displacement within the column and surrounding soil，respectively. Based on the results of the two-dimensional deformation analysis，solutions are developed for the consolidation of composite ground by comprehensively considering an instantly applied load，the combined flows along both the radial and vertical directions and three possible variable patterns of horizontal permeability of soil in distributed area. Finally，the consolidation behaviour of composite ground with two-dimensional deformation is investigated. The analysis results show as follows：(1) The degree of consolidation of composite ground predicted by the present solution with two-dimensional deformation is less than that calculated by the previous solution with only the vertical deformation under the same calculation conditions. (2) The column-soil stress ratio predicted by the present solution increases gradually during the consolidation process；but unlike the results predicted by the previous solution with one-dimensional deformation，it will not go up to the column-soil compressive modulus ratio but cease increasing at a smaller value. (3) Unlike the traditional solutions with one-dimensional deformation，the column-soil stress ratio at the initial moment predicted by the present solution with two-dimensional deformation is not equal to zero.
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2011, Vol. 30 
