Investigation of Spudcan Penetration Resistance in Layered Soil Deposits

다국어 초록 (Multilingual Abstract)

A suite of 3D large deformation finite element (FE) analyses was performed to investigate the load transfer mechanism and penetration resistance of spudcan foundations in heterogeneous soil profile consisting of sand and clay. The Elasto-Plastic models following Mohr-Coulomb and Tresca failure criteria were adopted for sand and clay, respectively. The accuracy of the numerical model was validated against centrifuge test measurements. The dense sand behavior with dilation is modeled using the non-associated flow rule. An investigation study consisting of key parameters, which includes variation in soil stratigraphy (sand-clay, sand-clay-sand), strength parameters of sand and clay (ϕ ′ and su) and normalized height ratio of the sand layer (Hs/D) was conducted to assess the penetration behavior of spudcan. Based on calculated outputs, it was demonstrated that these parameters have a significant influence on the penetration resistance of spudcan. The calculated penetration resistance profiles are compared with the published (sand overlying clay) analytical model. It is confirmed that for the case of two-layer soil, the available theoretical model provides an accurate estimate of peak penetration resistance (qpeak). In the case of three-layer soil, the presence of a third stiff layer affects the penetration resistance profile due to the squeezing of the soil.

목차 (Table of Contents)

• ABSTRACT
• 1. Introduction
• 2. Semi-Empirical Model for Prediction of Penetration Resistance of Spudcan
• 3. Representative Site Profile of Korea
• 4. Finite Element Model
• 5. Validation of Numerical Model with Centrifuge Results
• 6. Results and Discussion
• 7. Conclusions
• References

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