Effect of Spacing and Penetration Length of Prefabricated Vertical Drain on Consolidation Settlement of Soft Soil

Abstract Surcharge load with prefabricated vertical drain (PVD) is a special soft soil improvement technique. The utilization of this technique leads the soft soil to reach the ultimate consolidation settlement effectively since it can save the time and cost for embankment construction. The effectiveness of using surcharge load with PVD to enhance the ultimate consolidation settlement of the soft soil is strongly dependent on the soil properties, surcharge load, the configuration of PVD such as spacing and penetration length. The current study investigates the effect of PVD spacing and penetration length on the consolidation settlement of the improved soft soil via finite element analysis program, Plaxis 2D 2017. The results showed that the soft soil with PVD different spacings as 1.0 m, 1.5 m and 2.0 m produced similar results for the ultimate consolidation settlement and the excess pore water pressure. In addition, this study also figured that PVD penetration lengths seemed to not affect remarkably the consolidation process of the improved soft soil when the PVD penetration length was 50%, 75% and 100%. It is noted that the results of the current study were based on a finite element analysis program. In the future, further laboratory and field tests should be carried out to better understand the consolidation settlement of the soft soil that subjected to surcharge load and improved by PVD as the vertical drains.