INVESTIGATING OF THE BEHAVIOR OF PILE GROUPS UNDER THE EFFECT OF SUCTION POTENTIAL OF UNSATURATED EXPANSIVE SOIL

الملخص

This research presents an experimental study and numerical modelling to investigate the load-carrying capacity of a group of piles embedded in unsaturated expansive soil. The experimental work consists of a model of group of piles tested under unsaturated condition. The matric suction of the soil is measured by the Tensiometers to estimate the soil water characteristic curve (SWCC) by applying a fitting method. The experimental model is performed to validate the numerical modeling of the investigated problem using finite element method. A three-dimensional numerical modelling of a large-scale model is adopted to perform a parametric study on a group of piles in unsaturated expansive soil to investigate the effect of different parameters, such as depth of phreatic surface and initial degree of saturation on the load- carrying capacity. The results showed that a good agreement for the validation process. In addition, the load-carrying capacity increases when the depth of phreatic surface from the ground surface increases, also the decreasing in the initial degree of saturation of the soil lead to an increase in load-carrying capacity.