Effect of Adding Surcharge Load Stress on the Acceleration of Soft Soil Consolidation

Abstract

One type of soil that needs to be considered is soft soil. Soft soil has characteristics of large compression, long consolidation time, and low bearing capacity. Soft soil can be overcome using soil improvement methods to accelerate consolidation by using Surcharge Load coupled with Prefabricated Vertical Drains (PVD). This research uses GeoStudio 2018 software to determine how the addition of surcharge load to the embankment will affect the consolidation of soft soil. Modelling in GeoStudio is done using the Sigma/W model with the type of material model in the original soil using the Soft Clay model. The results of the analysis will be presented with a graph showing the relationship between the amount of settlement (m) and the settlement time (days). The results of the analysis were varied based on three surcharge load height models, namely 1.25 m, 2.50 m, and 3.50 m. The settlement is taken when the degree of consolidation has reached 90% (U90%). The time required to know the degree of consolidation has reached 90% is taken from the relationship graph of pore water pressure (PWP) with time. When the pore water pressure has dropped and has not changed, it is assumed that the degree of consolidation has reached 100%, therefore the days needed to reach 90% consolidation degree can be known. From the results of the analysis using Soft Clay material, a decrease of 0.71 m, 0.79 m, 0.86 m was obtained with the time to reach U90% for 88 days.