Comparative Life Cycle Assessment of Ultra-High Performance Concrete with Graphene Oxide

Several studies have been conducted on Ultra-High Performance Concrete (UHPC) to enhance the mechanical properties of this construction material, but the benefits of this new material to the natural environment is still to be assessed. So, this study aims at comparing the environmental impacts of conventional concrete and UHPC with graphene oxide (GO) by applying life cycle assessment (LCA). Four scenarios were considered in the LCA: (1) conventional concrete, (2) UHPC without graphene, (3) UHPC with a low content of GO, and (4) UHPC with a high content of GO. The compression strength for these scenarios was 30 MPa, 160 MPa, 160 MPa, and 180 MPa, respectively. The LCA was carried out in four phases: goal and scope definition, Life Cycle Inventory (LCI), Life Cycle Impact Assessment (LCIA), and Result Interpretation. For impacts per m³ of concrete produced, scenarios with UHPC (scenarios 2, 3, and 4) led to a much higher environmental impact (2,5 times higher) for most of the impact categories compared to conventional concrete results (scenario 1). For impacts per MPa of compression strength, the UHPC scenarios showed a much lower environmental impact than scenario 1. Notably, the higher strength UHPC, with the higher content of GO (scenario 4), resulted in a lower environmental burden due to a higher increase in strength due to the GO addition compared to the increase in impact. Therefore, UHPC with GO has a high potential to support more environmentally friendly construction if it results in less demand for concrete.