3. Heat treatment of concrete

3.1 General

The addition of thermal energy during setting accelerates concrete hardening. This thermomechanical coupling, often referred to as thermo-activation, can be put to good use on construction sites and, above all, in precast plants. In 1983, Marc Mamillan wrote, in the introduction to the previous version of this article: "... heat treatment is the most effective way of obtaining the strength required for demolding in just a few hours...". Today, this is no longer entirely true. The development of high-performance concretes, with the use of admixtures and mineral additives (in particular silica fume, which is now a component of certain cements), has shown that it is possible to obtain very high mechanical strengths at ages of less than 24 hours (the target times are often...