Experimental study of the bearing capacity of a drainage pipe pile under vacuum consolidation

In this study, we propose a drainage pipe pile under vacuum consolidation to integrate foundation treatment and pile foundation engineering in soft soil areas. To study its bearing capacity characteristics and foundation treatment performance, single pile static load tests, vane shear tests, and water content tests were carried out for ordinary piles, perforated piles, and drainage pipe piles under conditions of static and vacuum consolidation. Based on the results, the concept of strong and weak reinforcement areas was proposed and used for bearing capacity prediction. The results showed that the drainage pipe pile did not become silted under vacuum consolidation. The single pile bearing capacity was much higher than that of an ordinary pile, and the pile side friction was exerted mainly in the middle and lower parts. Good results were achieved using the shear strength at the junction of the strong and weak reinforcement areas to estimate the ultimate bearing capacity of a single pile. This study provided important insights into the design and construction of drainage pipe piles in a soft soil foundation.