Clayey Soil Reinforced with Stone Column Group: Model Tests and Analyses

Fully drained, load-controlled laboratory model tests and their numerical simulations are presented. The tests were performed on adequately instrumented, small scale physical models of floating stone column group foundations placed in slurry deposited clayey soil beds with known effective stress states. Effect of various group foundation parameters, such as area ratio, length of columns, relative density, and moisture content of the column material is evaluated. The numerical analyses consist of three-dimensional, elastoplastic, finite-element analyses of the model foundation. In the analyses, the clayey soil behavior is represented by the modified Cam-clay model, and the stone column and mat are represented by the elastic, fully plastic Mohr-Coulomb constitutive relationship. The finite-element analysis was successful in predicting the model test results with reasonable accuracy. The results are presented in nondimensional form. The major foundation parameters affecting the group response were identified as area ratio, normalized column length, Young's modulus of column, overconsolidation ratio, initial geostatic stresses, and clayey soil parameters. DOI:10.1061/(ASCE)GT.1943-5606.0000552. (C) 2011 American Society of Civil Engineers.