The Effect of Geonet Reinforcement on Bearing Capacity of Low-Compacted Soft Clay

In this paper, we studied if geonets, when used for drainage purposes, can also contribute to the bearing capacity of clay. For this purpose, extensive laboratory testing and numerical modeling were performed on various configurations to investigate the effect of geonet on the bearing capacity of low-compacted soft clay. Physical models built with four footing shapes (square, rectangular, and two circular) along with several configurations of the reinforcement layout (i.e., number, length, spacing, and depth of reinforcement layers) were tested in the laboratory. Moreover, finite element modeling was performed and the results were compared with those obtained from the laboratory tests. It was found the geonet reinforcement can improve the bearing capacity of low-compacted clay up to six times more than its natural condition. The results showed that the optimum reinforcement length for the single-layer model is 3B (where B is the width of footing) and beyond this length, no significant improvement was observed. However, for the two-layer and three-layer models, the optimum length of reinforcements was found to be 2B. To maximize the benefit of the reinforcement, it was found that the first, second, and third reinforcement layers should be placed at the depths of B/3, B/2, and B, respectively. Among different footing shapes which were tested, the square footing showed the highest bearing capacity improvement with a bearing capacity ratio of 7.6. Very good agreement was observed upon comparison of the results from the numerical modeling with the experimental tests.

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