Mechanical properties and corrosion resistance of concrete modified with granite dust

Granite dust is a waste material produced during cutting and polishing process of granite products. This research work presents an experimental investigation on physical, mechanical properties and reinforcement corrosion resistance of concrete modified with granite dust. The cement pastes modified with granite dust were examined using TGA, X-ray and SEM. Granite dust cement replacement or addition of 5.0%, 7.5%, 10.0% and 15.0% were used. The test results showed an improvement on concrete compressive strength at 5.0% granite dust as cement replacement and improvement on compressive strength at most levels of granite dust as cement addition. The tensile strength test results are confirmed the test results of concrete compressive strength. Also, the use of 5.0% granite dust increased the corrosion cracking time and no significant reduction in cracking time was observed at granite dust contents greater than 5.0%. Insignificant changes in hydration products, microstructure and degree of hydration due to using granite dust were observed. Finally, a reduction in water cement ratio around 0.03 was enough to cancel the reduction in concrete compressive strength as a result of granite dust up to 15.0% as cement replacement.