Model tests on red clay foundation reinforced by coir geotextiles

Abstract

Geosynthetics slowly degrade in soil, which may cause environmental problems in the future. Natural coir fibers are green, environmental-friendly, renewable, and have broad application prospects. Coir geotextiles were used to reinforce red clay foundations. The effects of the reinforcement length and depth, first-layer reinforcement depth, and reinforcement-layer spacing on the deformation and bearing capacity of the foundations were studied via load tests. The distribution law of the earth pressure along the depth was also analyzed. The results showed that when the reinforcement length was 1B, the anchorage length of the reinforcement was insufficient, and the reinforcement effect was unclear. As the reinforcement length increased, the anchoring length of the reinforcement increased, and bearing capacity of the foundation significantly increased. However, when the reinforcement length exceeded 3B, the force of the anchorage segment was fully exerted, slightly increasing the bearing capacity of the foundation. The optimal reinforcement length was determined as 3B. The bearing capacity of the foundation increased as the reinforcement depth increased and the buried depth of the first reinforcement layer and spacing of the reinforcement decreased. The optimal reinforcement depth, buried depth of the first reinforcement layer, and reinforcement spacing were 2B, 0.25B, and 0.25B, respectively.