Estimating the Geotechnical Design Pararameters of Improved Soil by Preloading Method Using Instrumentation Results and Numerical Approach- a Case Study

Document Type : پژوهشی

Authors

• Khosrow Mehrshahi
• Hamid Alielahi

Islamic Azad University

10.22067/civil.v1i30.52137

Abstract

In his paper, back-analysis using rsults from instrumentation by finite element software for design of preloading method by embankment with prefibricated vetical drains (PVDs) was used, and the results were compared with each other. Hence, the basic geotechnical parameters obtained by laboratory and field experiments have been modified using this method. In this regard, the Mahshahr oil storage project has been used as a case study. All of the methods that are used for improving soil must ultimately result in increased soil resistance parameters, reduced compressibility, and reduced soil permeability. The soil improvement technique using preloading was used in Mahshahr where there are soft soil layers beneath higher than sub-surface water. control performance of the embankments, some instruments such as Settlement Plates and Piezometers have been used. The results obtained from the analysis shows that settlement parameters obtained from the instruments data by back-analysis were less than primary consolidation settlement parameters based on laboratory tests. Finally, soil settlement estimation of the oil tank was compared before and after preloading, and it was found that using this method for soil improvement can be very efficient in the current project.

Keywords

• Preloading Method
• Radial Drains
• Consolidation Settlement
• Numerical Approach

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