Investigation of the Consolidation Behavior of Soft Soil Improved with Vertical Drains by Finite Element Method

Abstract

The primary consolidation may take long time due to the low permeability of clay soils in such cases soil improvement may be required to shorten the consolidation time, increase shear strength, and therefore bearing capacity. Preloading is one of the commonly used methods to consolidate soils before actual load and to strengthen weak compressible soils. In cases with time problems, the use of prefabricated vertical drains (PVD) with pre-loading shortens the drainage path and reduces the consolidation time by taking advantage of the horizontal permeability of the soils is generally higher. In this study, an embankment constructed at different load rates with constant accelerates and analyzes were performed for the non-drained and drained conditions of clay soils with PVDs are in 2m, 1m, and 0.5m intervals. In this way, the effect of load rate and PVD usage on consolidation settlement and excess pore pressures in underlying low permeable clayey soil was investigated.

Keywords

• Soft Clay
• Consolidation
• Load Rate
• Prefabric Vertical Drain
• Finite Element Method

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