Thermomechanical Damage Analysis of Pre-cooled Wind Tower Foundations: Experimental and Numerical Study

The finite element method (FEM) is the preferred approach to model transient temperature evolution in mass concrete structures. However, FEM requires heat generation curves obtained experimentally and field validationto ensure accuracy. This study presents the experimental characterization and numerical simulation of temperatureevolution in wind tower foundations. Five pre-cooling methodologies, including liquid nitrogen (LN) and ice flakes,were evaluated for efficiency and cost. Semi-adiabatic calorimetry tests were conducted to obtain heat generationcurves, alongside compressive strength tests. A field study compared FEM results with measured temperatures fromfour wind tower foundations. Additionally, a parametric study assessed each cooling technique. All pre-coolingmethods yielded mixtures with higher compressive strength than the reference, except the ice flakes mixture. The FEM model accurately captured temperature evolution based on heat generation rates, confirmed by field measurements.Cooling aggregates with LN proved to be the best-performing methodology but was also the most expensive. Acombination of LN and ice flakes offered a good balance of efficiency and cost. A continuous damage model (Mazars) was applied to assess thermal strain effects, revealing significant variation in maximum theoretical damage acrosscooling methods. These findings highlight the importance of balancing temperature control and damage distribution when selecting pre-cooling techniques for wind tower foundations.