CONSOLIDATION BEHAVIOUR OF MIX CLAY USING LAURENT TRANSFORM

Abstract

Consolidation behaviour of fine grained soil is evaluated commonly by Terzaghi’s one dimensional linear elastic consolidation theory. It is based on several simplified assumptions. Out of these assumptions most important assumption is constant value of coefficient of consolidation Cv during the consolidation process. But it leads serious problems to the consolidation of soft clay like bentonite and bentonite –sand mixture. Since Terzaghi’s one dimensional consolidation theory gives good results for small strain problems. Hence in this study Terzaghi’s one dimensional consolidation theory is used for evaluating consolidation of pure bentonite and bentonite –sand mixture assuming constant value of coefficient of consolidation Cv for small range of effective stress. Variation of coefficient of consolidation with effective stress for different percentage of bentonite in sand is shown. Moreover variation of other consolidation properties like coefficient of compressibility av, coefficient of volume compressibility mv, compression index Cc with effective stress is determined and comparison of these properties for different clay content are made. Based on consolidation property permeability of clay is calculated indirectly for different percentage of clay. It is observed that permeability of clay increases with decrease in clay content.Based on consolidation properties graphs between average degree of consolidation and time factor is plotted and comparison is made for different percentage of clay. Rate of consolidation is compared here using the two transforms Fourier as well as Laurent and it is clear from the experiments that rate of consolidation is faster using Laurent transform.