3.1 Soil preparation
The soil used for validation was sourced from the toe of mountains in the campus of Indian Institute of Technology Guwahati campus, India. Guwahati located in the northeastern part of India, experiences sub-tropical climate. The soil consisted of sand (13 %), silt (65 %), and clay (22 %). The liquid limit and plastic limit of the soil were measured as 32.0 % and 24.8 %, respectively. According to the Unified Soil Classification System (USCS), the soil was identified as CL (sandy lean clay). As per the standard compaction tests (ASTM D 1140), the maximum dry density and optimum water content were found as 1.66 g/cm3 and 18.8 %, respectively. Table 1 summarized the basic properties of the soil.