Environmental impact assessment of post tensioned and reinforced concrete slab construction

In Australia, approximately 30 million tonnes of finished building products are produced each year, with over 56% of this quantity, by mass, being attributed to concrete and a further 6%, steel, highlighting the importance of maximising design efficiencies. The cement industry has been reported responsible for 5% of global carbon dioxide emissions while the construction, operation and maintenance of buildings are estimated to account for 50% of all energy usage and more than 50% of all anthropogenic greenhouse gas (GHG) emissions globally. This research determines some environmental advantages achievable through application of alternate concrete slab construction methods for a typical 10-storey office structure. Structural analysis results indicate a 36.9% reduction in concrete volume and 43.4% reduction in steel mass in a post tensioned slab structure in comparison with a conventional reinforced slab system. Similar results were observed when comparing reductions in embodied energy and global warming potential. These results highlight the improvements possible by the incorporation of improved sustainable design methods.