Document Type : Article
Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran.
This paper presents the swelling and consolidation characteristics of Lignosulfonate (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, optimum percentage of LS for treatment of this clay was determined 0.75% by soil dry weight. To investigate swelling and consolidation properties of untreated and LS-treated remoulded samples, one dimensional swell and consolidation tests were conducted on these samples. Test results showed that LS has 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 behavior to the changes of compaction moisture content due to the altering of soil expansivity category from high to moderate. The SEM images of samples showed that the soil specific area was reduced because of stabilization. This reduction in soil specific area was led to the decrease of affinity of samples to moisture increase, so the volume change of expansive clay was decreased.