Stability analysis method of geogrid reinforced expansive soil slopes and its engineering application

Abstract

The traditional stability analysis method of geogrid reinforced slopes does not consider the effect of lateral swelling, so it is not applicable to reinforced expansive soil slopes. This paper reports a new stability analysis method for geogrid reinforced expansive soil slopes. The additional pullout force of the free zone due to the lateral swelling and the anti-pullout safety factor of each geogrid layer were obtained by ensuring the overall stability of the reinforced slope. The optimum design was carried out to treat an expansive soil cut slope in Hubei Province, China, by changing the spacing and length of geogrid reinforcement. Calculation results show that the additional pullout force caused by lateral swelling has a great influence on the anti-pullout stability of geogrids, and the local stability of the reinforced slope will be overestimated if the swelling effect of soil in the free zone is not considered.

Keywords

expansive soil / lateral swelling pressure / geogrid-soil interaction / stability analysis / engineering application

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