Chotan Chowdhury
Dr. Md. Zahid Husain Khan
Abstract
Construction of highway embankments on soft clay soils is seriously crucial trouble for the serviceability of subgrade projects. It is a great concern to predict the settlement of the embankment on soft soil. Generally, Geotechnical problem is found where the soils are composed of soft clay. In this case, it is needed to predict the Consolidation settlement of clay. The prefabricated band drains are used for accelerating the consolidation of soft soils. During the Construction of high-way problems on soft soil, it is required to analyze stability related to the reduction of consolidation settlement. In this work, empirical methods of Prefabricated Vertical Drains (PVDs) & Preloading are used to analyze the settlement comprehensively. By the technique of preloading, consolidation of soil can be achieved to a considerable amount before applying of actual construction load. The result of the settlement analysis of the Highway Embankment in the research area is 248 mm, which takes almost 21 years for primary consolidations to achieve a 95% degree of consolidation. To reduce the duration of consolidation settlement Prefabricated Vertical Drains(PVDs)and Preloading are applied. The Kjellman formula is used for the estimation of the consolidation time. A triangular pattern is adopted in the depth of 19 m with a spacing of 1m and the reduced time for primary consolidation settlement is almost 120 days.
Keywords
Consolidation; Soft Clay Soils; Settlement; Preloading; Prefabricated Vertical Drains
