Volume change behavior of stabilized expansive clay with lignosulfonate

This paper presents the swelling and consolidation characteristics of ligno-sulfonate (LS) stabilized expansive clay. Expansive clay samples of Amol city in Iran have been used in this research. Based on Atterberg limits and unconfined compressive strength tests, the optimum percentage of LS for the treatment of this clay was determined at 0.75% by soil dry weight. To investigate the swelling and consolidation properties of untreated and LS-treated remolded samples, one-dimensional swell and consolidation tests were conducted on these samples. Test results showed that LS had considerable effect on the consolidation and swelling behavior of the expansive clay. Moreover, the effects of compaction water content change and cyclic wetting and drying on the volume change properties of unstabilized and LS-stabilized samples were investigated. Untreated and LS-treated specimens showed different consolidation behaviors towards the variations of compaction moisture content due to the alteration of soil expansivity category from high to moderate. The Scanning Electron Microscope (SEM) images of samples showed that the soil specific area was reduced because of stabilization. This reduction in soil specific area led to the decrease of affinity of samples to moisture increase; thus, the volume change of expansive clay decreased. (C) 2020 Sharif University of Technology. All rights reserved.