DBPapers
DOI: 10.5593/sgem2017/12/S02.019

CONSOLIDATION PROPERTIES OF COHESIVE SOILS IN THE RED RIVER DELTA IN SALT-AFFECTED CONDITIONS

T.N. Ngoc
Sunday 10 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7105-99-5 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 12, 143-150 pp, DOI: 10.5593/sgem2017/12/S02.019

ABSTRACT

Saline intrusion related to drought and sea level rise may result in changing of engineering properties of cohesive soils. To comprehend the variation of geotechnical properties of soils intruded by saline water, consolidation is one of the important aspects should be investigated. Undisturbed soil samples that originated from sediment in the Red River delta, Vietnam, were chosen. In the conditions that soils had been fully saturated by solution of four salt concentrations, 0.0, 9.9, 19.8 and 33‰, the variation of geotechnical parameters of the soils were verified. Consolidation of soil specimens change almost proportionally to the concentration of saline water. Namely, coefficient of consolidation decrease proportionally to salinity, meanwhile compressibility index and secondary compression index increase with the same conditions. The change of consolidation properties of the cohesive soils in the Red River delta in saline media is believed to be related to clay mineral composition. The presence of expandable clay mineral together with a series of physico-chemical interactions bringing about neutralizing of negative charge of clay is considered as reason of those changes.

Keywords: Saline intrusion, Red River delta soils, salt-affected soil, consolidation, deformation modulus