Hydromechanical Behavior of a Tuff/Bentonite Mixture Treated with Cement

Demdoum A., Daheur E. G., Loualbia H., Bounouara Z., Ghembaza M. S., AKGÜN H.

6th International Conference on Geotechnics, Civil Engineering and Structures, CIGOS 2021, Hạ Long Bay, Vietnam, 28 - 29 October 2021, vol.203, pp.1103-1112 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 203
  • Doi Number: 10.1007/978-981-16-7160-9_112
  • City: Hạ Long Bay
  • Country: Vietnam
  • Page Numbers: pp.1103-1112
  • Keywords: Bentonite, Tuff, Permeability
  • Middle East Technical University Affiliated: Yes


© 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Sandy soil-clay mixtures are commonly used as a liner/barrier material in various engineering applications, such as construction of hydraulic and waste containment. In this study, the hydromechanical characteristics of tuff-bentonite and tuff-bentonite/cement mixtures are investigated to propose a local barrier material. A series of free swelling, one-dimensional consolidation and falling head permeability tests for hydraulic characteristics as well as the direct shear test for mechanical characteristics were performed on four different tuff-bentonite mixtures and two different tuff-bentonite/cement mixtures. Test results show that the compressibility/swelling behavior of the mixtures increases with increasing bentonite content. The optimum amount of bentonite to achieve a permeability of less than 10–9 m/s, which is a liner/barrier design requirement, was found at 8% and 10%. The results of the strength tests indicate that the apparent cohesion increases with the bentonite content, while the apparent angle of friction decreases. Concerning the optimal mix treated with 3% and 5% cement, the test results show that the permeability and compressibility/swelling behavior decrease with the added cement content, while the angle of friction and cohesion increase. Finally, it was concluded that the 8% bentonite-92% tuff mixture treated with 3% cement is retained as a passive barrier material for landfill sites in arid and semi-arid regions.