Abstract
A main reason why we do research on autogenous deformation (AD) is that we want input to the assessment ofearly age cracking risk, often used calculation programs. It is however a great challenge to model the properties involved, the AD and in particular, for input to calculation programs, as it is the nature of early age concrete that it changes from liquid to a solid and that the temperature changes considerably due to heat of hydration. AD is extremely temperature dependent, and, importantlisothermal data can hardly be used to predict the behaviour during realistic temperature histories. this difficulty is even more complex when adding mineral additives, as they may change the temperature dependency. Hence, AD should be measured at the realistic temperature histories.