Mechanical properties and mineralogy of artisanal clay bricks manufactured in Dididi, Limpopo, South Africa

Abstract

The mineralogical changes in sun-dried (raw), fired and burnt bricks were investigated using XRF, XRD, SEM-EDS and FTIR while their compressive strength and water absorption capacity was determined and compared to specifications as prescribed by the South African National Standard SANS 227:2007 and ASTM C34-13 respectively and to the commercialised clay bricks. Also addressed was the issue of environmental pollution. It was found that the kaolinite present in the sun-dried was transformed into metakaolinite, spinel in the fired and cristobalite and mullite in the burnt respectively. The compressive strength for fired and burnt bricks were found to be 4.3 MPa and 9 MPa while water absorption was 16.5% and 9.8% respectively.