Energy foundation technology is expected to make a significant contribution to the use of renewable energy. In this context, this paper presents the use of Finite Element simulation using PLAXIS software for modelling different benchmark applications in Geothermal Foundations. An implicit fully-coupled numerical scheme with global adaptive time stepping are implemented to ensure computational efficiency and stability. Firstly, a transient simulation of thermal response tests [1], often used to estimate the thermal conductivity of ground and thermal resistance of pile, is presented. In the second part, a Thermo-Hydro-Mechanical analysis is performed to simulate the behavior of a single heat pile subject to a thermal load cycle [2]. Several ingredients (constitutive behavior, interface finite elements etc.) are employed to simulate soil-structure interactions. The obtained solutions are validated against available simulation and experimental data to demonstrate the applicability of the simulator to energy foundation analysis and design.@en

Thermal and Thermo-Hydro-Mechanical (THM) analysis is at the core of a broad range of geotechnical engineering applications. In this context, an implicit fully coupled formulation has been implemented in the Finite Element software PLAXIS to perform robustly THM analyses. Advanced constitutive models can be easily defined and implemented with the well-known User-Defined Soil Model (UDSM) module. Recently, another module of User-Defined Flow Model (UDFM) has been developed so that users can implement user-defined fluid and heat transfer models (permeability, thermal conductivity functions etc). These improvements allow to perform advanced research analyses in a practical and user-friendly way. In this paper, the aforementioned formulation and functionalities are briefly summarised. Different examples of benchmark numerical analyses of Engineered Barrier Systems (EBS) in radioactive waste disposals as well as geothermal foundation systems are then presented. The obtained numerical results are verified by comparisons with other simulators and/or experimental data.@en