Fresh and hardened properties of cement paste and mortar incorporating calcined cutter soil mixing residue

Abstract

Supplementary cementitious materials (SCMs) have been widely used in modern concrete technology to improve the sustainability and performance of concrete, but the concern over the decreasing supply of conventional SCMs in the future raises a need to explore their alternatives. This study aims to corroborate the performance of a calcined solid waste, i.e., cutter soil mixing residue (CSMR), as a new SCM in sustainable cementitious materials. The rheological behaviors, hydration kinetics, pore structures, physico-mechanical properties, and durability of cement paste and mortar blended with calcined CSMR were experimentally investigated. Results showed that the calcined CSMR powders with a lower specific surface area than the cement particles could improve the flowability of the cement paste. The calcined CSMR exhibited higher reactivity than the coal fly ash and could accelerate the cement hydration, create additional hydrates, and refine pore structures. Adding 20% calcined CSMR in the cement mortar had negligible adverse effects on the compressive strength, dry shrinkage resistance, electrical resistivity, and sulfate attack resistance. Meanwhile, the incorporation of 15–30% calcined CSMR reduced the embodied energy and carbon emissions of the cement mortar by around 13–25%. Overall, this research demonstrated the possibility of using calcined CSMR as a new SCM to develop greener cementitious materials without compromising the engineering properties.