Volume 36, N. 2, May-August 2013 | PDF(14 downloads)
. One of the most important morphological characteristics of expansive soil is contracting and fissuring during drying and swelling during wetting. Soils that change volume when inundated with water require extra care, whether they are used in agriculture, engineering or both. In this paper, conventional and suction-controlled oedometric tests were used to evaluate the changes in volume and swelling pressure caused by changes in water content in an expansive soil from PetrolÃ¢ndia-PE. A coupled hydro-mechanical formulation, implemented in the computational code CODE_BRIGHT, was applied to simulate the tests performed with this soil. The constitutive model used was the double structure generalized plasticity model proposed by Sanchez et al. (2005). The results show that soil expansion, contraction and collapse depend on the initial water content and the external load applied. The conclusion is that volume changes due to water content variation are associated with the initial conditions of the soil and the load applied to the soil. The experimental data and simulation results are in good agreement, showing that the model and computer code are able to accurately represent the hydro-mechanical behavior of expansive soils.