Load Carrying Capacity of Expansive Clay Beds Reinforced with Geogrid-Encased Granular Pile-Anchors

Plate load tests were conducted on unreinforced expansive clay beds and clay beds reinforced with Granular Pile Anchor (GPA) and geogrid-encased GPA to compare their compressive load response. It was found from the tests that the expansive clay beds reinforced with geogrid-encased GPA showed higher load-carrying capacity and improved compressive load response compared with GPA and unreinforced beds. The applied pressure to cause a settlement of 25 mm in the unreinforced clay bed and clay bed reinforced with GPA of length 97 mm and diameter 30 mm (\( \frac{{l_{gp} }}{{d_{gp} }} = 3.23 \)) was respectively 152.78 kPa and 789.4 kPa, showing an improvement of 416.7%. However, the clay bed reinforced with geogrid-encased GPA required a pressure of 858.16 kPa for the same amount of settlement. This shows an improvement of 461.7% with respect to the unreinforced clay bed. Among three types of anchors used in this study, the one with a length of 97 mm and a diameter of 30 mm showed the best load response when tested without geogrid, resulting in an improvement of 659.3% whereas, the same GPA showed a better improvement of 955.57% when encased with geogrid.