COMPRESSIBILITY CHARACTERISTICS OF SOFT CLAY USING LARGE SIZED MODEL CONSOLIDATION TEST THROUGH VERTICAL GEO-DRAIN

The present study is an attempt to determine consolidation characteristics of soft saturated kaolinite clay using large size consolidometer with aspect ratio 1.0:0.635. In the present investigation two drain material viz. sand and LLDPE granules are used as central drain with inward radial flow of 'n' value equal to 10. Further Barron's equal strain (plain strain) theory is adopted to validate experimental results for vertical drain and is compared with virgin soil. Settlement computed from conventional consolidation test with aspect ratio (1:4/1:3) is compared with large size consolidometer with aspect ratio (1.0:0.635). Effect of large thickness of remoulded clay sample and pore water pressure mobility can be better understand through this study using vertical drains and its comparison with 1D vertical flow of conventional Oedo-meter. Pre and post vane shear strength are recorded and shear strength results are compared with virgin clay. Results indicate little variation in degree of consolidation computed from Barron's theory and efficacy of sand drain is much higher than LLDPE granules.