Analytical and experimental study of the expansive soil behavior which exposed of several cycles of shrinking and swollen
This research includes an experimental and numerical study of swollen soils that are subjected to repeated cycles of swelling and shrinkage, and the problem of this soil appears when it is moistened and dried, as a result of the volumetric changes that occur to it, which leads to damage to foundations and engineering facilities. The research was applied to swollen soil from Syria, and moisturizing and drying cycles were applied using the hydrometer experiment, by immersing the sample in water for the hydration phase, and for drying a device was designed that dries the sample to the required temperature and for the time we want, until the soil reaches the equilibrium phase after several cycles and no longer gives the soil any Volumetric changes, then we conducted a numerical study using the finite element method of the swollen soil to which the experimental study was applied, and we found a good convergence between the experimental measurements and the numerical results. Where we developed a suitable numerical model for the issue based on modeling the mean of soil diffusion and the forces affecting it using the Plaxis2020 calculation program to model the behavior of swollen soils subjected to multiple cycles of wetting and drying, using the Barcelona Basic Model, which is the numerical model dedicated to modeling the behavior of swollen unsaturated soils depending on the parameters The experimental model, and the results of the research showed a decrease in the amplitude of swelling and shrinkage until reaching stability after the third cycle of wetting and drying, as well as the prolonged swelling when applying an external load that is initially small and then returns and rises in the second cycle of wetting the sample, the results of this research enable us to avoid many risks of soil swelling By applying multiple cycles of wetting and drying before construction, thus stabilizing soil deformations to a large extent, and the results of the research allow predicting the volumetric changes of the swollen soil and the number of cycles required to reach the stability phase before practically starting building on the soil, thus assessing the potential impacts on people and neighboring facilities and taking the necessary measures When necessary, to avoid them, so that we can benefit from this etc. A guide in preserving the integrity of buildings established on swollen soils.