Acceleration of Consolidation of Soft Clay Layers with Prefabricated Vertical Drain (PVD) Method

Abstract

Soil consolidation settlement is a geotechnical problem often found in embankment cases, especially on soft soils. The decrease in consolidation is caused by the release of pore water from the soil caused by increased stress in the soil mass. Soft clay is a cohesive soil which is the largest part of the soil consisting of very small grains such as clay or silt. The properties of the soft clay layer have a small shear force. Based on the soil test in the laboratory, the density was 2.75, the coefficient of compression (Cc) was 0.40, and the coefficient of expansion (Cs) was 0.03, so it was classified as soft clay. From the results of calculations without using PVD that have been carried out, the time needed to reach the 95% consolidation degree is 60 days with a decrease of 7 cm. Meanwhile, by using PVD, the time required is 30 days with a large reduction of 15 cm. From the analysis that has been done, it can be concluded that the use of PVD can accelerate the consolidation time