There is an increase in bulk density values with increasing drainage cycles, which can be related to the function of clay with the reduction in water content. There is a reduction in drainage with an increase in wetting and drying cycles, which is observed with the help of water retention curves. In case of zero variant, the water retention curve obtained is almost a straight line (i.e., even though there is presence of water, it cannot be drained). This could be due to the water holding capacity of clay. With the amendment of 100% lime and 100% FGD gypsum drainage is observed even after 20 wetting and drying cycles. Drainage observed is more with 100% FGD gypsum compared to that of 100% lime indicating amelioration success with the use of FGD gypsum to be more efficient.

Amelioration with different amendments is well achieved in the case of 100% FGD gypsum in comparison with 100% lime. The values of cohesion and angles of internal frictions of the shear lines are smaller. Cohesion constants are almost same in case of zero variant, 100% FGD gypsum and 100% lime variants but the angle of internal friction is higher in case of 100% FGD gypsum variant in comparison to 100% lime variant. With increase in drainage cycles cohesion and angle of internal friction increased along with the shear stress. With cohesion values being less FGD gypsum or lime addition can not prevent erosion. This increase in shear stress could be due to the increased aggregation with drainage cycles.

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