This paper focuses on the evolution of the thermal characteristics of
early-age concrete as a function of the state of the hardening process
. A literature review is presented, together with new test results obt
ained by means of improved test methods: For the determination of the
specific heat of cement paste during hardening and of the thermal diff
usivity of hardening concrete, test methods are developed based on exi
sting methods. The specific heat is determined for hardening cement pa
ste samples made with blastfurnace slag cement. It is concluded that t
he specific heat and thermal diffusivity decreases linearly with the d
egree of hydration.