Thermal Gradient in Large Concrete Test Bodies: A Macroscale Experimental Approach

Abstract

The objective of this study is to reproduce, with large size laboratory concrete specimen, the non-uniform heating that is naturally observed in some civil engineering structures. The aim is to obtain a reliable predictive model, making it possible to evaluate the risk of developing certain pathologies such as Delayed Ettringite Formation (DEF) due to the temperatures reached and their distribution in the concrete. To this end, the dimensions and characteristics of the formwork were first determined from numerical simulations. Then, the formwork was supplemented with sensors to record the temperatures in the three spatial directions over time. The results showed that the sensors recorded a high temperature in the core of the specimens, exceeding 80 ℃, and that there were large temperature variations between the surface and the core of the concrete.