Influence of ground granulated blast furnace slag on cracking potential of high performance concrete at early age

Abstract In recent years, high performance concrete (HPC) has been fully developed and put into widespread use in the actual project. Ground granulated blast furnace slag (GGBFS) has been widely used in HPC as a mineral admixture to improve the comprehensive workability. Nowadays, Temperature Stress Test Machine (TSTM) has been used to investigate the cracking potential of concrete. The influence of GGBFS on the early-age cracking potential of HPC has been investigated. However, investigations on the influence of GGBFS on the early-age cracking potential of HPC under adiabatic condition at full uniaxial restraint degree by using TSTM remain lacking. Investigations on the early-age cracking potential of HPC with different GGBFS contents (0%, 20%, 35%, and 50%) under adiabatic condition at full uniaxial restraint degree by using TSTM were conducted in the present study. The experimental results and related analysis indicated that (1) the addition of GGBFS reduced early-age temperature rise, temperature drop, cracking stress, cracking temperature, and stress reserve of HPC; (2) the autogenous shrinkage and integrated criterion of HPC increased with the increasing GGBFS content at early age; (3) the early-age cracking potential of HPC increased with the increasing GGBFS content, and the optimal GGBFS content shall not exceed 20% in the present study.