Bearing capacity of reinforced horizontal sandy ground

Abstract

In order to develop a method of predicting the bearing capacity of horizontal sandy ground reinforced with tensile-reinforcement layers horizontally placed beneath a footing, a series of plane strain model tests with a strip footing was performed. The effects of the length, the arrangements and the rigidity and rupture strength of reinforcement were examined systematically. The strain fields in sand, the tensile forces in reinforcement and the distribution of contact pressure on footing were measured. Even by means of reinforcement layers with a length similar to the footing width, the bearing capacity increased remarkably. Also, the portions of reinforcement layers located outside the footing width contributed to the increase in the bearing capacity only in a secondary way. The bearing capacity of reinforced sand was found equal to the smaller of the following two values; the one controlled by the failure of the reinforced zone immediately beneath the footing and the other by the failure of sand beneath the reinforced zone. Based on the test results, a method of stability analysis by the limit equilibrium method was developed, taking into account the effects of the arrangement and properties of reinforcement and the failure modes of reinforced sand. The predicted values were well in accordance with the measured ones.