Mechanical properties

This chapter report the most recent experimental results on mechanical behaviour at high temperature of high-performance concretes. After a short introduction, Sect. 5.2 describes the main testing methods that were used in the analysed studies. Section 5.3 collects and compares the temperature-dependency of the compressive strength and modulus of elasticity of many experimental studies. The influence of parameters such as the initial compressive strength, the type of aggregate, the presence of additions, the W/C ratio, the moisture content and the way the mechanical test was performed is analysed. Section 5.4 presents the experimental results obtained under a constant temperature, i.e. creep tests at high temperature. Section 5.5 presents experimental results obtained under increasing temperature. These results allow assessing the free thermal strain of concrete (when no mechanical load is applied) and the so-called “transient thermal strain”. Finally, Sect. 5.6 collects and analyses the few results concerning the temperature-dependency of the tensile strength of high-performance concretes