ABSTRACT
This chapter provides an overview of the availability and usage of coarse aggregate in the construction industry in South Africa where a unique blend of First and Third World developments can be found. Several quartzite bodies are utilized for coarse aggregate in the Gauteng region; however, those from the Pretoria area in the north have somewhat different characteristics to those quarried in the south. The dolomite available in the Gauteng region is considered a good coarse aggregate as concretes made with this aggregate have high test prism crushing values, low drying shrinkage and fairly low abrasion values. Andesite has been used in all aspects of road construction, but tends to polish and is therefore not well suited to road surfacing. The fresh granite available in the Gauteng region is an acceptable concrete aggregate, and despite the fact that the water absorption is relatively high for an igneous rock, the drying shrinkage is low.
