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| Consolidation analysis of stone column-impervious pile composite ground underneath rigid foundation considering radial and vertical flows within stone columns |
| YANG Tao1，LI Chao2 |
(1. Department of Civil Engineering，University of Shanghai for Science and Technology，Shanghai 200093，China；
2. Institute of Geotechnical Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China) |
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Abstract The equal vertical strains were assumed and the smear effect in subsoil surrounding the stone columns and impervious piles and the well resistances in the stone columns in vertical and radial directions were considered，so that the differential equations governing the consolidation of stone column-impervious pile composite ground were derived under the instant loading. The corresponding analytical solutions were developed under the PTIB condition，including the overall average degree of consolidation of this type of combined composite ground. The proposed solution was verified through the comparison with the results from finite element method. A parametric study was conducted using the proposed solution to investigate the consolidation behavior of the composite ground. The results show that the consolidation rate of the soft ground improved by the stone columns combined with impervious piles is much faster than that of the composite ground with impervious piles，but slightly slower than that of the composite ground improved by stone columns. The consolidation rate increases with increasing of the area replacement ratio and constrained modulus of the stone columns or the impervious piles，but decreases with the increasing of the two- dimensional well resistances in the stone columns when the diameter of the stone column is bigger. The effect of the radial well resistance on the consolidation rate is negligible when the diameter of the stone column is smaller. The disturbance of the subsoil surrounding impervious piles has negligible influence on the consolidation rate of the composite ground.
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2018, Vol. 37 
