Correlation between dynamic mechanical thermo-analysis and composition-based models for C-S-H in hydrated portland cement paste

Abstract

A dynamic mechanical analysis (DMTA) technique was used to assess the mechanical performance of 1.4 nm tobermorite (T), jennite (J) and mixtures of tobermorite and jennite and tobermorite and calcium hydroxide (CH). A comparison of E′ (storage modulus) and tan∂ (internal friction) versus temperature curves for compacted solid bodies of these mineral systems with corresponding curves for cement paste hydrated for 2 month and 3 years (both referred to as ‘young’) and 45-year-old paste (referred to as ‘old’) was made. Original data was provided to assess the practical validity of the Richardson–Groves composition-based models for the C-S-H in cement paste. Differences in mechanical performance between the ‘young’ paste and the ‘old’ paste could be accounted for by application of a T/J dominant model (‘young’ paste) and a J–T/CH structural model with a minor amount of T (‘old paste’).