Influence of Leachate on Properties and Regions of Compacted Clay Layer: A Column Experiment

ABSTRACT

This study examines the properties of clay in contact with leachate from municipal solid waste at different depths in the clay column, based on experiments using a physical model. The parameters of the clay microstructure were quantitatively measured. Changes in the clay properties were determined based on the seepage process and reactions of leachate with the clay. Results indicate that there are three zones in the clay column from top to bottom: region in contact with the leachate, region where chemical reactions take place and an unaffected region. In this study, it shows that there is a critical threshold seepage depth which influences the properties of the compacted clay. That is, there are distinct changes in clay properties with depth. The critical threshold depth of the clay column in this study is 23 cm, that is, the amount of leaching is the highest at the depth of 23 cm, which has the most detrimental impact on the clay properties.

KEYWORDS:

• Compacted clay layer
• changes in properties
• leaching
• contamination process
• seepage

Additional information

Funding

This study is supported by the National Natural Science Foundation of China [No.41372326, 41072236], the Fundamental Research Funds for the Central Universities [2014ZDPY27], and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.