SOIL SUBSTANCE ANALYSIS USING PVD WITH VACUUM CONSOLIDATION METHOD (VCM)

Abstract

The construction of toll roads on soft clay has the main problems of the relatively low bearing capacity of the subgrade and the relatively large and long duration of subgrade compression. The infrastructure built on the subgrade could be damaged before it reaches its planned age if the subgrade not repaired first. The selection of the soft clay soil handling method considers the cost and time at the time of construction in the field. For this reason, alternative methods needed that are cost and time efficient and have minimal risk to environmental impacts. The vacuum consolidation method (VCM) is an alternative to improve water saturated soft clay. Soil improvement using the vacuum consolidation method is intended to accelerate the settlement and increase the bearing capacity of the soft native soil by vacuum pumping the soil to reduce the moisture content and air content of the soil grains to accelerate long-term settlement and differential settlement. This study aimed to analyze the soil settlement using PVD with the vacuum consolidation method (VCM). The analysis conducted showed that to achieve 90% consolidation without PVD, it would take 13,922 years and using PVD, it would take 18 months, and using PVD and the vacuum consolidation method (VCM), it would take 4,8 months. The use of PVD with the vacuum consolidation method (VCM) can speed up the consolidation process compared to using PVD or only using PVD. The total decrease that occurred was 2,043 m.