Design de pieux et mouvements de terrain.

Abstract

The design of the piles that oppose the movement of the ground can be made using different methods. Pressure or displacement based methods as well as numerical methods have prevailed over the design of piles for a long time. Kourkoulis et al. (2012) proposed a new concept regarding the design of stabilizing piles. this concept consists of a hybrid methodology that combines analytical approaches in slope stability, with three-dimensional finite element numerical analysis. This method was developed only to analyze piles placed in the middle of unstable slopes and for a minimum spacing between piles S = 2D (spacing equals two times the diameter of pile). The applicability of the hybrid method for the analysis and design of the slope stabilizing piles placed at the toe of the slopes and contiguous pile walls is the subject of the present research. The decoupled model of the hybrid method was also used for the analysis of helical piles subjected to ground movement. The code Abaqus was used for the different simulations. The simplified model for the analysis and design of stabilizing piles placed at the toe of the slopes and the contiguous pile walls showed a coherence with that applied for the piles located in the middle of the slope. Regarding the performance of the helical piles subjected to ground movement, it was found that the helices, called also plates, placed near the slip surface move with the pile because of the soil mass movement. This movement mobilizes the soil reactions under and above the helices, creating a resisting moment that increases the resistance offered by the helical piles. The presence of plates does not only lead to an increase in the resistance force, but also to a decrease in the pile head deflection.