Models for Predicting Free Water and Specific Heat of Pastes Containing Ground Granulated Blast Furnace Slag

Abstract: This paper aims to investigate early age behavior in terms of free water content and specific heat for hardening cement paste incorporating Ground Granulated Blast Furnace Slag. Experiments were conducted to obtain free water and specific heat of slag-cement pastes by varying water to binder ratios and slag replacement levels. Free water to total binder ratios for pastes with w/b of 0.40 and slag replacements of 45% and 75% are 0.23 and 0.25 at 3 days and 0.17 and 0.19 at 28 days, respectively. Specific heat values for similar mixtures are 0.26 and 0.30 at 3 days and 0.23 and 0.25 at 28 days. Results showed that specific heat decreases as the amount of free water decreases. The slag substitution resulted in high specific heat and free water at early age but tends to decrease in long term due to enhanced reaction kinetics. Models were proposed to compute free water and specific heat by modifying existing models. The model simulations can be used to predict the measured values accurately

Models for Predicting Hydration Degree and Adiabatic Temperature Rise of Mass Concrete containing Ground Granulated Blast Furnace Slag

Predicting adiabatic temperature rise is essentially useful for investigating thermal cracking potential especially in early stage of mass concrete.  Existing prediction methods and models have some problems such as constant thermal properties are mostly utilized for predicting temperature rise. This study is aimed to develop time-dependent models for predicting hydration degrees of cement and slag, free water amount, specific heat, and total heat generation of concrete incorporating slag.  These models are then composed to predict the adiabatic temperature rise of mass concrete incorporating slag.  The model is able to predict adiabatic temperature rise in mass concrete with different water to binder ratios, slag replacements, physical properties of slag, and initial temperature conditions.  The validity of the proposed model was evaluated by comparing the model predictions with test results for adiabatic temperature rise of slag concrete.  The model simulations can be used to predict the experimentally measured data from differentPredicting adiabatic temperature rise is essentially useful for investigating thermal cracking potential especially in early stage of mass concrete.  Existing prediction methods and models have some problems such as constant thermal properties are mostly utilized for predicting temperature rise. This study is aimed to develop time-dependent models for predicting hydration degrees of cement and slag, free water amount, specific heat, and total heat generation of concrete incorporating slag.  These models are then composed to predict the adiabatic temperature rise of mass concrete incorporating slag.  The model is able to predict adiabatic temperature rise in mass concrete with different water to binder ratios, slag replacements, physical properties of slag, and initial temperature conditions.  The validity of the proposed model was evaluated by comparing the model predictions with test results for adiabatic temperature rise of slag concrete.  The model simulations can be used to predict the experimentally measured data from differen