Influence of Vetiver Root System on Mechanical Performance of Expansive Soil: Experimental Studies

Table 1

Basic parameters of the test soil.

Index	Optimum water content (%)	Maximum dry density (g·cm^−3)	Free swelling ratio (%)	Plastic limit (%)	Liquid limit (%)	Plastic index
Value	20.5	1.56	50	23.9	53.5	29.6