Behaviour of a Strip Footing Embedded in a Sand Slope Reinforced with Multilayer Geotextile

Abstract

This paper presents the results of laboratory model tests and numerical analysis on the behaviour of a strip footing embedded in a multilayer geotextile-reinforced sand slope. The investigation was aimed at determining the effect of footing embedment depth $D$ and number of geotextile layers $N$ on the bearing capacity and settlement characteristics of an embedded footing. The results show that the load–settlement behaviour of the embedded footing is significantly affected by $D$ and $N$. The advantage of reinforcing the slope with more than one geotextile layer and placing the footing below the slope crest has been evaluated using a non-dimensional parameter, called the ultimate bearing capacity ratio ${\text{BCR}}_{u}$, defined as the ratio of ultimate bearing capacity of the reinforced case to that of unreinforced case. It is observed that ${\text{BCR}}_{u}$ improves with an increase in $N$ but reduces with an increase in $D/B$, where $B$ is the footing width. The minimum ${\text{BCR}}_{u}$, ${\text{BCR}}_{u} (\hbox{min} ) \approx 2$ is observed for $N = 1$ and $D/B = 1$, while the maximum ${\text{BCR}}_{u}$, ${\text{BCR}}_{u} (\hbox{max} ) \approx 6$ is attained when the footing is placed at $D/B = 0$ and $N = 3$. A comparison between the numerical and laboratory test results shows a very good agreement.