Analysis Of Soil Improvement With Combination Of Prefabricated Vertical Drain And Vacuum Consolidation Using Program (Study Case: Palembang – Indralaya Toll Road Section 1 Sta 0+000 – 1+000)

Abstract

Palembang - Indralaya toll road that located in Kab. Ogan Komering Ilir, Sout Sumatera was built on soft soil. Soft soil with its characteristic such as low permeability, high compressibility and low bearing capacity is not suitable for construction since soil settlement can occured and become a threat for the structure above it. So, a soil improvement action is needed in order to meet the criteria of the construction.

The method that will be used is combination of vacuum consolidation method with PVD and soil preloading with PVD to accelerate the consolidation of the soil. This method is done by applying the vacuum pressure to the soil through the PVD that has been installed. It goes the same with preloading where the soil fill will act as additional load to the soil. This research aim is to determine the consolidation time and soil settlement value.

The result for this research that were obtained shows that combination of vacuum consolidation method and prefabricated vertical drain can accelerate the consolidation time. The result is soil settlement of 0.387 m for 47 days on 90% consolidation by using PVD triangle pattern with 1 m space while without PVD took 21.9 years. From the result, the PVD triangle pattern with 1 m space is the most effective PVD pattern.