Back analysis of a collapsed highway embankment – A numerical study on the rigid reinforcement and time-dependent grouting

Abstract

A sliding accident occurred in the embankment slope of a highway in the south of China. The cause of the failure was investigated based on the geological data, construction conditions and numerical results. Measures were taken to reinforce the embankment including loading berm, steel pipe grouting and steel sheet pile. The applicability of the reinforcements and the stability of the reinforced embankment were analyzed through numerical simulation. A scheme for the time-dependent slurry diffusion was proposed. The grouting process was realized in the numerical model through extensive programming, and the diffusion range of the cement slurry with the duration of grouting can be monitored in the numerical model, whereby the effect of the grouting was evaluated. The paper not only can provide valuable hints for the research relating to the stability analysis of slopes, but also are instructive for the treatment of sliding accidents in the soft soil embankments in the area of heavy rainfall.