Strength performance and life cycle assessment of high-volume low-grade kaolin clay pozzolan concrete: A Ghanaian scenario

Abstract

Concrete, the highest consumed construction material in the world is known to be the third leading contributor to carbon dioxide and other greenhouse gas emissions (GHG) aside from energy generation and transportation. These GHGs are known to be the governor of global warming and climate change. Therefore, the United Nations has taken it vital work to reduce GHG emissions from around the globe. In this work, C30 class of concrete was produced with five different types of binders using replacement levels of cement at 0, 10, 20, 30, 40, and 50 wt%. The formulated concretes containing the pozzolans were compared with OPC concretes in terms of strength performance and total carbon dioxide emissions. The results of the study revealed that concrete containing up to 50% pozzolan meets the C30 concrete grade even at late age curing of 90 days. In terms of carbon emissions, pozzolan concrete proved to be a means of decarbonizing traditional concrete. The OPC concrete recorded the highest carbon emission value of approximately 511 kg CO2eq. whereas the 50% pozzolan concrete recorded the least carbon dioxide emission value of approximately 335 kg CO2eq. The study recommends the utilization of the pozzolan as a cost-effective means to decarbonize regional concretes for enhanced global sustainability