A study on the strength and durability of cement mortar featuring partial brick powder replacement: economic and sustainability implications

Abstract

This investigation explores the potential of clay brick powder (CBP) as a partial alternative to cement in mortar compositions, concentrating on the effects of the fineness of CBP, which is produced by grinding brick waste for various durations. A range of mortar mixes was analyzed for characteristics including apparent density, porosity, spreadability, ultrasonic pulse velocity (UPV), flexural and compressive strength, and pozzolanic activity index. The analysis reveals that grinding CBP for 60 minutes leads to a mortar spread that exceeds 95% relative to the reference mix. The addition of CBP enhances water absorption and porosity, yet it does not considerably influence the apparent density. Most of the mortar samples demonstrated satisfactory mechanical characteristics, achieving a UPV near 4000 m/s. While replacing 20% of cement with CBP causes a decline in flexural strength, this decrease is mitigated when the specific surface area of CBP is comparable to that of cement. Assessments of environmental and economic factors demonstrate that integrating CBP into cement formulations leads to a marked reduction in energy usage and CO₂ emissions. Specifically, replacing 20% of cement with CBP of varying fineness levels offers significant environmental benefits and economic practicality.