Increasing the sustainability potential of a reinforced concrete building through design strategies: Case study

This paper aims to investigate the influence of design strategies on the economic and environmental performance of 30-storey residential reinforced concrete (RC) building located in the Southern Brazil, through a case study. Four design options are simulated for the same building, including structural design as rigid frame system or hinged frame system with second order/P delta effects. In both cases buildings were designed with concrete strength class 25 MPa (C25) applied in all the structural elements or a concrete strength class range of 50 MPa to 25 MPa (C25-C50) applied in columns, varying along the building height. Environmental impacts were quantified through Life Cycle Assessment (LCA) based on measurements of environmental loads of processes and products, from cradle to grave. Results show reduction of environmental impacts, embodied energy and construction costs when a decrease in the amount of steel is combined with the increase in the concrete compressive strength of columns, which is more representative for the building designed as hinged frame system. The production of materials phase showed to be the major contributor to environmental impacts with steel and concrete being the most relevant impact producers. Concrete represents important impacts for stratospheric ozone depletion and climate change while steel dominates the ecotoxicity-related indicators. Results highlight the importance of design strategies to increase the sustainability potential of a RC structure and contribute to consolidate contemporary approaches that suggest the need to incorporate the degree of environmental impacts in design methods.