ABSTRACT
Soft clays pose a significant challenge to engineers due to their low strength and potential for large settlement. The characteristics of soft clay can be significantly improved with the application of electro-osmosis. The bearing and lateral capacity of steel model piles installed in a soft clay stratum treated by electro-osmosis was investigated in the present study. A comprehensive investigation was undertaken utilizing an applied voltage corresponding to 50 V /m, and a configuration of four electrodes surrounding a central pile (D = 61 mm). The electrodes were made of steel pipes (d = 9.5 mm) with holes drilled every 20 mm and a spacing of 2D from the central pile. The electro-osmotic treatment was performed using both a constant DC electric field and a current intermittence of 1 min on I 1 min off, for a period of seven days. The experimental tests consisted of both small scale and large scale tests to assess the effectiveness of the treatment to pile capacity for a soft clay. Initial results from the small scale test indicate that while the shear strength of the soil surrounding the pile was significantly increased, the bearing capacity of the pile was in fact decreased. This indicates that the pile/soil adhesion factor, Ca was significantly reduced during the treatment process, most likely due to over-treatment of the soil immediately adjacent to the pile. Thus it is paramount in the treatment of piles with electro-osmosis to determine the appropriate treatment time to be utilized.
