Phreatic Surface Estimation In MSE Wall With Geocomposite Back Drainage

This study proposes a simple mathematic model for approximating the level of phreatic surface inside the protected zone in mechanical stabilized earth wall with back drain installation though the position of phreatic surface at the drainage interface ( h o ) which reflects the maximum level of phreatic surface in the protected zone. The proposed model was established based on dataset taken from 180 simulation cases caried out in Plaxis environment. Regression results present a combination of significant effects and major role to maximum water level in the protected zone ( h o ) of a ratio of length from upstream water to the drainage face to the wall height ( L/H ), a soil permeabilities coefficient (k) and a transmissivity of the drainage material ( T net ). The proposed model can facilitate design of drainage material to achieve desired level of phreatic surface in the protected zone.