Analyzing the early structural build-up of accelerated cement pastes

Abstract Extrusion-based additive manufacturing imposes high requirements on the material stability right after extrusion. Therefore, a thorough understanding of chemical reactions that determine early reduction in processability is necessary. Accelerators are especially considered here, which have major influence reaction. This study contributes to these issues by analyzing 0.1 wt% TEA (triethanolamine) and 2.0 Ca(NO 3 ) 2 hydration two CEM I 52.5 R. The was analyzed isothermal heat flow calorimetry in-situ X-ray diffraction. Vicat needle penetration, penetrometer own design, ultrasonic P-wave velocity development were used monitor change workability. obtained results indicate ettringite formation main factor influencing workability during first 60 min hydration. Afterwards, exceeded C–S–H. shown enhance C–S–H had no significant effect while rapidly decreasing induction period. increase brownmillerite dissolution and, consequently, promote loss initial time final setting determined test depended mainly phases.