NAPL Permeation Tests of Shanghai Saturated Clay Using Consolidation Permeameter

Abstract:

In non-aqueous phase liquid（NAPL） permeation test of saturated clay，NAPL-clay interactions can lead to sample shrinkage and sidewall leakage，which affects the reliability of the test results. Kerosene permeation tests using consolidation permeameter were conducted on Shanghai mucky clay to investigate the influence of vertical consolidation pressure p_v and the soil structure on sidewall leakage and test results. The test results show that for intact samples with a flocculation structure， sidewall leakage occurred at p_v = 50 kPa and 200 kPa， resulting in an overestimation of permeability coefficient， while reliable test results can be obtained at p_v = 400 kPa. However，for remolded samples with a dispersed structure，sidewall leakage still existed even at p_v = 400 kPa. Based on the pore distribution of the intact soil sample and the test results at p_v = 400 kPa，the characteristics of NAPL permeation in Shanghai mucky clay are discussed in detail. These results are valuable for understanding the migration characteristics of NAPL pollutants in coastal soft clay.

Key words:non-aqueous phase liquids(NAPL);permeability test;saturated clay;sidewall leakage;consolidation permeameter