Stability of multi-anchor soil walls after loss of toe support

Abstract

This paper reports the results of a novel experiment in which two nominally identical full-scale steel multi-anchor reinforced soil walls were taken to foundation failure by progressive loss of footing support. The 4-m high walls varied only with respect to reinforcement anchor lengths. The data show that facing displacements at end of construction and at time of foundation failure below the footing were greater for the wall with the shorter reinforcement lengths. Reinforcement loads at end of construction were best estimated using a working stress model proposed by the authors rather than current methods used in Japan and the UK. However, after significant loss of footing support, the Japanese Public Works Research Centre method gave more accurate and safer load predictions. Regardless, both the anchor rods and anchor plates had abundant reserve capacity to provide large margins of safety against internal tensile rupture and pullout modes of failure even after large foundation displacements.