Skip to content

Prefabricated Vertical Drain with surcharge is a widely used method of soil improvement to accelerate the consolidation of soft soils. In such applications, discharge capacity is an important parameter to determine the effectiveness of the prefabricated vertical drains. Hence many manufacturers of prefabricated vertical drains and researchers developed their own drain tester to determine discharge capacity. Hansbo ( 1983) described what an “ideal test” should be for a standard drain tester. This paper consists of a brief review of six drain testing device, including the ASTM recommended prefabricated vertical drain test device. The features of each test device is compared to the “ideal test” defined by Hansbo. The sixth drain tester is a new device developed at National University of Singapore (NUS), and this will be discussed in detail in the paper.