CONICET | Buscador de Institutos y Recursos Humanos

The aim of this study is to evaluate the efficiency of calcium lignosulfonate (CLS) as a soil stabilization agent. Additives are used for treating different types of soils. These improve soil?s physical, hydraulic and mechanical properties. Traditionally, inorganic additives such as lime, cement or fly ash are used for roads and highways? base materials, embankments and foundations. The use of polymeric additives within the infrastructure industry is still in the research stage, whereas they have been extensively implemented in agriculture, in arid and semi-arid areas, to control fine migration and improve water retention.CLS as a soil stabilization agent was mixed with a highly expansive soil from Comodoro Rivadavia (Argentina). This soil particularly exhibits plastic volumetric behavior when subjected to moisture gradient [1]. These instabilities can damage light weight constructions, such as houses, some of which were reported by Orlani et al. [2].To assess CLS ability to control this soil?s expansion it was mixed using three different weight proportions:1.5, 3.0 and 5.0 % by weight of soil. Firstly, physical and mechanical parameters of the soil-CLS mixture were measured (Atterberg limits, Cation Exchange Capacity, and Specific Surface Area). Furthermore, hydromechanical characterization of the mixtures was performed. Free swelling and swelling pressure were determined. In addition, Scanning Electron Microscopy and Mercury Intrusion Porosimetry tests were carried out to evaluate changes in microstructure due to soil-CLS interaction.Tests show that the addition of a small amount of CLS to this soil can satisfactorily control its expansibility. In addition, the mixtures registered an increase in soil stiffness and compressibility, higher strength on failure,and porosity reduction among others.