Utilization of Dredged Mud in Land Reclamation: A Comparison Study of Several Soil Improvement Methods

Abstract

Utilization of dredged mud in land reclamation will become more applicable in the future due to the increase of the need for space and the rising cost of granular fill materials. Dredged mud mainly consists of soft clay and has very low bearing capacity and high compressibility. Therefore, soil improvement is urgently required. In this paper, the effectiveness of using dredged mud as the fill material in land reclamation was analyzed for a case study of land reclamation. The performance of several soil improvement methods in using such reclamation material was calculated and compared. The soil improvement methods considered in this study were prefabricated vertical drain (PVD) with vacuum preloading, cement mixed dredged mud, and rigid inclusion. The load transfer mechanism in each method was analyzed using analytical and numerical methods. In addition, an elementary cost analysis was performed to compare the cost of the methods based on Indonesian prices. It was found that for the considered case study, cement mixing achieved the highest bearing capacity with the shortest time but with the highest cost. For the same increase in bearing capacity, PVD with vacuum preloading provided the lowest cost. This study provides a preliminary step towards the implementation of effective soil improvement for land reclamation in Indonesia.