Uji Fisik dan Numerik Model Kombinasi Preloading dan Prefabricated Drain pada Tanah Lempung Lunak

Abstract

Soft clay soil is cohesive soils comprising the largest portion of land which consists of grains that are very small such as clay or silt . The nature of the soft clay layer have small shear force , a large congestion , small coefficient of permeability and low carrying capacity than other clay . so , when the load exceeded the carrying capacity of the critical construction , there will be damage to the foundation. According to soil test in laboratorium obtained that spesific gravity amount 2.75, coefficient of compression (Cc) amount 0.40 and coefficient of swelling (Cs) amount 0.03 so that is classified as a soft clay.Adding embankment as preloading from its characteristic which plotted from drawn plan. With adding prefabricated drain, is expected to make rate of consolidation become rapidly. Laying prefabricated drain have ratio of transversal and longitudinal distances with symmetric configuration amount 1/3 from length of embankment model with horizontal direction and have ratio of length prefabricated drain amount 2/3 from height of surface base soil. According to result of analysis plaxis obtained that maximum settlement amount 8.32 mm and accelerated the pace of consolidation up to 92.198% where the condition of excess pore water pressure at 1kN/m2.