Effect of curing temperature on hydration characteristics of GGBFS-based cementless high-strength concrete

Abstract

This research examines how curing temperature affects in the development of CaO-activated cementless GGBFS high-strength concrete. Compressive strength tests were conducted on samples cured at 50 degrees C, 70 degrees C, and 90 degrees C for 12 h, with additional evaluation after 3 and 28 days of water curing. TGA, FT-IR, NMR, MIP, and BET analyses further investigated the microstructural evolution. Findings show that higher temperatures significantly enhance pozzolanic reactions, leading to initial strengths of up to 95.6 MPa and maintaining high levels after 28 days. Elevated temperatures enhances the formation of denser and more stable hydration products, predominantly C-S-H, confirmed by spectroscopic analysis which relates with increased binder reactivity to enhanced compressive strength. Additionally, improved porosity refinement at higher temperatures correlates with increased strength. This research highlights the dual benefit of using cementless high-strength concrete: achieving substantial strength and reducing CO2 emissions, supporting its potential for high-strength applications with reduced environmental impact.