Quarry Southern Africa September 2017 | Page 26

Lower carbon, lower cost: the future of concrete By Robyn Grimsley As one of the most widely used materials on the planet, concrete presents an ideal opportunity for the industry to minimise its environmental impact. The Portside Tower is Cape Town’s tallest — and ‘greenest’ — building, with up to 85% substitution of cement with slag waste. 24 _ QUARRY SA | SEPTEMBER 2017