Abstract
This study investigates the effect of bitumen addition on the long-term permeability of bitumen mixed sabkha soil. Results will be used to evaluate the effectiveness of using the bitumen mixed sabkha soil as hydraulic barriers to leachate percolation. Eight percent bitumen (by dry weight of sabkha) was selected as a mixing percentage based on density results obtained from modified Proctor tests carried out on sabkha soil samples mixed with different bitumen contents. Long-term permeability studies using distilled water were carried out on undisturbed, natural compacted and 8% bitumen mixed sabkha soil samples. The results displayed significant reduction in the initial and long term permeability values of the 8% bitumen mixed sabkha, as compared to the natural compacted sabkha soil. The reduced permeability values of the 8% bitumen sabkha soil are still higher than the recommended value for soil liners. The results also clearly show that sabkha soil compaction, which is the general practice for liners preparation in Kuwait, is not an effective process.