Numerical Modeling of the Effect of Partial Penetration of Vertical Drains on the Consolidation Process, Case Study: Preloading of Sarbandar Decanter Units in Khoozestan

Document Type : Research Article


1 Associate Professor, Department of Civil and Environmental Engineering, Amirkabir University of Technology

2 Former MSc student, Department of Civil and Environmental Engineering, Amirkabir University of Technology


The most important factor in soil preloading is the consolidation time. In any cases, if installation depth of the vertical drain is less than the design depth (which is equal to the thickness of the compressible layer), a delay of the consolidation process will occur. In this paper, effect of this parameter on consolidation time is determined by numerical modeling and then a case study (soil preloading project of Sarbandar decanter units in Khoozestan) is studied. In some areas in this project, the penetrating depth of vertical drains is less than the expected design depth. Comparison has been made between numerical modeling and data from field instrumentation could be done.
It is concluded that if the penetrating depth of vertical drains is more than 80% of the compressible layer thickness, the delay in the consolidation process seems to be negligible.


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