Laboratory scale column experiment to study infiltration of hydrologic soil type after gravel amendment

The infiltration and percolation function in Low impact development technologies can be improved by soil amendment technique using different types of media. Therefore, laboratory scale column experiment was performed to study the infiltration rate of hydrologic soil type B, C, and D as case 1 and 25%, 50% and 75% of gravel amendment soil of its total depth was considered case 2, case 3 and case 4, respectively. The antecedent soil moisture content less than 15% was wet condition and higher was saturated condition. The wet experiment for case 2, case 3 and case 4 completed within 3 to 4 hours while case 1 lasted for 5 to 7 days. Furthermore, the mean infiltration rate of soil type B, C, and D for case 2, case 3 and case 4 ranges from 1.02 to 11 times higher than that of case 1. The higher infiltration rate was observed due to increase in the non-capillary void after gravel amendment (Johnson et al., 1963). On the other hand, the saturated experiment for case 2, case 3 and case 4 completed after 5 to 6 hours while case 1 lasted for 10 to 14 days. The soil moisture content causes swelling of clay thereby decreasing interstitial pores and infiltration rate (Johnson et al., 1963). The mean infiltration rate during saturated condition was decreased by 2 to 14 times lower than wet condition. After overall results and discussion, it can be concluded soil amendment can be valuable technique to improve infiltration mechanism.