A Vertical Electro-Osmosis Method to Improve the Bearing Capacity of Piles in Marine Soft Clay

A vertical electro-osmosis method was proposed to improve the bearing capacity of piles in marine soft clay foundations. A top-down electro-osmosis test was conducted by setting an anode and cathode at the top and bottom of the pile, respectively, while the settings of bottom-up electro-osmosis were set in the opposite way. At the same time, a pile without electro-osmosis was also set up for comparison. The variation law of water content, water discharge volume, soil pressure, and surface settlement of soil around the pile during electro-osmosis was tested and analyzed. A direct shear test and static load test were carried out to study the effects of vertical electro-osmosis on the shear strength of soil and the bearing capacity of the pile. The experimental results show that vertical electro-osmosis can significantly improve the bearing capacity of the pile and the shear strength of soil around the pile. The bearing capacity of the piles in the top-down electro-osmosis test was 16.7% higher than that in the bottom-up electro-osmosis test, and the amount of water discharged was 41.69% higher. Compared with the horizontal electro-osmosis around the pile, the vertical electro-osmosis had a faster drainage speed, better soil consolidation, and a slightly smaller increase in the bearing capacity of the pile. Because vertical electro-osmosis is easy to implement on concrete piles, the new method proposed in this study has a broad application prospect.