Substitution of sand ditch system method on vacuum preloading (study case: Land preparation project in Kalimantan)

Abstract

Vacuum Preloading is considered as an efficient method in soil improvement. It is complemented by the implementation of horizontal drain work, namely the Sand Ditch System and the Hand Type Connector. Decision making in the application of these methods must be adjusted to the actual needs and conditions in the project. This research was conducted in soil improvement projects in Kalimantan which was originally planned to use the Sand Ditch System. However, difficulties were found in finding sand as a media for draining water. Consequently, the method substitution was carried out to the Hand Type Connector. The purpose of this study indicate that the application of the Hand Type Connector Method is more effective and efficient in terms of cost and time compared to the Sand Ditch System. The cost and time required by the Sand Ditch System are respectively Rp 56.095,00/m2 and 194 days. Meanwhile, the costs and time required by the Hand Type Connector are respectively Rp 37.250,00/m2 and 183 days. Therefore, this project can save cost by 33,59% and time by 5,67%.