Abstract
This paper investigates the effects of dolomite-concrete powder (DCP) on the microstructure and strength development of alkali-activated brick waste. Raw DCP waste was used to replace alkali-activated brick waste at replacement ratios of 0%, 5%, 10%, 15%, 20% and 30% by mass. Similarly, raw DCP thermally treated at 800 °C for 2 h with a heating rate of 5 °C/min was also used to replace alkali-activated brick waste at replacement ratios of 0%, 5%, 10%, 15%, 20% and 30% by mass. The water/binder ratio and compressive strength of the samples were measured. Laboratory techniques of Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis along with its derivatives (TGA/DTG) and Scanning Electron Microscopy (SEM) were utilized for studying molecular and microstructure of hardened samples. The experimental results obtained in the present procedure showed the feasibility of using DCP for enhancing the mechanical properties and the microstructure of alkali-activated brick waste-based geopolymer.
•Concrete waste containing dolomite aggregate was used to improve the properties of brick-based geopolymer.•Geopolymer can be used to produce low-cost building units.•Alkali-activated pastes containing 20% DCP displayed superior compressive strength.•Inclusion of calcined dolomite concrete in geopolymeric matrix resulted in a more denser and impermeable microstructure.