A numerical method for predicting Young’s modulus of heated cement paste

•A numerical method is developed for predicting the Young’s modulus of heated cement paste.•Thermal decomposition analysis of cement paste is conducted.•The effects of thermal decomposition and microcracking on the Young’s modulus of heated cement paste are considered. The evaluation of the mechanical properties of heated cement paste is essential to the safety assessment of concrete structures exposed to elevated temperatures. A numerical method is developed in this paper for predicting the Young’s modulus of heated cement paste with or without silica fume up to 600°C. The initial volume fractions of various constituents and the thermal decomposition of hydration products in cement paste are approximately estimated. A two-phase composite sphere model is then built and a two-step approach is applied to evaluating the Young’s modulus of heated cement paste with thermal decomposition and microcracking effects. Finally, the validity of the proposed numerical method is verified with three sets of experimental data collected from the literature.