Influence of Lead Pollution on Cohesive Soil Erodibility using Jet Erosion Tests

摘要

Recent researches were investigated the high concentrations of Lead in Baghdad soils due to the emissions from Leaded fuel of cars, generators, and the industrials. These high concentrations in addition to their impact on human health may impact on the landscape and streambanks and may cause significant issues on soil erodibility. The erosion rate of cohesive soil was usually estimated using two alternative models, excess shear stress model which is depended on two major soil parameters: the critical shear stress, τc, and the erodibility coefficient, kd, and Wilson model which is depended on two mechanistic soil parameters: b0 and b1. A new miniature version of Jet Erosion Test (“mini” JET) was performed to derive both model parameters. The objective of this study was to investigate the influence of Lead pollution on cohesive soil erodibility using “mini” JET under controlled laboratory setups to predict soil erodibility. In order to observe the Lead contamination on soil erodibility, soil samples were mixed with different quantities of Lead concertation and the samples were packed at ASTM standard mold on two different bulk densities. Results show that the Lead pollution increased soil erodibility when the concentration of Lead increased. An inverse relationship between excess shear stress parameters kd and τc was observed as well as between Wilson model parameters b0 and b1. The Wilson model parameters were closely resembled the empirical excess shear stress parameters with benefit that Wilson model parameters are mechanistic parameters.