Experimental study on discharge capacity of prefabricated vertical drain considering interaction of PVD and soil

In order to study the practical discharge capacity of prefabricated vertical drain (PVD), a new apparatus is developed. The laboratory vacuum preloading model tests, surcharge preloading model tests and direct filling tests are used to produce the PVD-soil element samples, and the discharge capacity measurements of PVD-soil element samples are conducted. The test results show that regardless of using the direct filling tests, laboratory vacuum preloading tests and surcharge preloading tests, the discharge capacity of high-performance PVD is higher than that measured by the current specification, and that of the traditional PVD is lower than the value measured by the current specification. The results by the current specification overestimate the discharge capacity of the traditional PVD under vacuum preloading. The comparative test results reveal that the discharge capacity of the high-performance PVD under surcharge preloading is close to that under vacuum preloading, and the discharge capacity of the traditional PVD under surcharge preloading is higher than that under vacuum preloading. Therefore, for the newly dredged soft soil reinforcement project, when the settlement of soil is large and the consolidation period is long, the high-performance PVD should be preferred.