Abstract: Adiabatic temperature rise rate is the key factor affecting the adiabatic temperature rise of concrete. Indoor adiabatic temperature rise test was carried out on fly-ash (content 35%) concrete. The test was controlled with three initial temperatures and five water-binder ratios. The influence rules of initial temperature and water-binder ratio on the adiabatic temperature rise and the rise rate were examined. The standard of dividing three stages of adiabatic temperature rise rate was put forward. A three-stage model of adiabatic temperature rise rate of medium-volumed fly ash concrete was established. The model takes into consideration water-binder ratio, initial temperature and age, and predictes accurately the adiabatic temperature rise rate at each age.The results can provide reference for temperature adiabatic controlling of mass concrete.

Key words: adiabatic temperature rise, rate of adiabatic temperature rise, fly-ash concrete, initial temperature, water-binder ratio, three-stage model