This paper presents the results of Unconfined Compressive Strength tests (UCS)
carried out on clay soils stabilized with Lignosulfonate (LS). Laboratory studies
indicate that lignosulfonate can increase the stiffness of the treated soils. Moreover,
the influence of clay minerals on the LS stablisation is investigated using Fourier
Transform Infrared (FTIR) Spectroscopy and Electrical Conductivity (EC). The
analysis confirms that the clay mineralogy plays an important role in the stabilisation
of clay soils. The stabilization mechanism is mainly due to the formation of
lignosulfonate-clay amorphous compounds through the electrostatic reaction process.