Carbon emissions assessment of ultra-high performance concrete in construction industry: Calculation method and case study

The promotion of high-performance concrete in engineering can significantly reduce carbon emissions in the urban construction industry, which is essential for achieving green and sustainable development goals. However, the specific contributions of ultra-high performance concrete (UHPC) and ultra-high performance concrete with coarse aggregate (UHPC-CA) have not been thoroughly investigated. To accurately quantify the carbon emission benefits of UHPC and UHPC-CA, the carbon emissions calculation method considering the influence of multiple factors for the main aboveground structure construction has been proposed. A specific 11-story reinforced concrete frame structure (RCFS) is selected for the case study. Subsequently, the carbon emissions of various types of concrete under five designed building construction programs are calculated and evaluated. Additionally, the cost-effectiveness and performance benefits are discussed concurrently. Based on an actual engineering case, this study comprehensively evaluates the environmental, cost, and performance benefits of using UHPC, UHPCCA, and ordinary concrete in the construction industry. The results indicate that both UHPC and UHPC-CA can reduce carbon emissions while enhancing the performance benefits of the RCFS and lowering construction costs. Specifically, UHPC-CA can reduce carbon emissions and construction costs by 20% at equivalent performance, while UHPC can improve performance by 76% at equivalent costs, with a 6% increase in carbon emissions. The engineering value of UHPC and UHPC-CA is remarkable, characterized by significant reductions in carbon emissions, ultra-high performance, and superior durability.