Shaking table modeling of MSE/soil nail hybrid retaining walls

Abstract

A series of 1-g shaking table tests using variable-amplitude harmonic excitations was performed on 0.8-m-high MSE/soil nail hybrid retaining (MSE/SN) wall models to investigate the seismic behavior of this innovative retaining earth structure. The tests were conducted on physical wall models with strips having a constant length and different nail lengths under loading conditions with different peak accelerations and durations. It was found that the deformation mode and the horizontal displacements of the MSE/SN walls were highly dependent on the length of the nails, such that L/H = 0.7 can be defined as the critical ratio in seismic conditions for MSE/SN walls which have been reinforced with strips having a constant length. Irrespective of the different nail lengths, the pattern of the observed failure mechanism included a moving block which was delineated by a two-part failure plane consisting of a concave curve and an inclined line with a certain point of intersection. Also, a consistent range of the normalized horizontal displacements (Δx/H), about 0.55–1.10%, corresponding to the formation of local shear bands, and a range of Δx/H = 5.0–5.6%, corresponding to the development of active wedge failure, were determined.