Numerical investigation of behavior of energy piles in saturated fine-grained soil

Document Type : Research Article

Authors

Department of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran

Abstract

The current study aimed to examine the behavior of energy piles in saturated fine-grained soils using the finite element method. The proposed thermo-hydro-mechanical model could demonstrate the energy pile behavior in most practical conditions such as under thermal, mechanical, or thermomechanical loading. Based on the obtained results from this study, the thermal expansion of the pile and temperature variation in the soil affect vertical effective stress in the soil. Since vertical effective stress is an important parameter in estimating bearing capacity and consolidation settlement of the bearing system and controls the stability of the superstructure, the effects of thermal loading on vertical effective stress of soil and consequently, on the bearing capacity of pile needs to be investigated accurately. For this purpose, a comprehensive parametric study was accomplished. Based on the results, the elastic modulus, Poisson ratio, thermal expansion coefficient of solid grains, void ratio, and coefficient of permeability of fine-grained soil were the most important and effective parameters on bearing capacity and consolidation settlement of energy piles in saturated conditions. Based on the results, the elasticity modulus of the soil has a significant effect on reducing the vertical effective stress of the soil by up to 40 percent of the initial in-situ stress.

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References

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AUT Journal of Civil Engineering
Volume 8, Issue 2
2024
Pages 145-160

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