Comparative study on carbon emission of steel and aluminum alloy structure greenhouse building in whole life cycle

Based on case study on a greenhouse building, this paper systematically quantifies and analyzes the difference of carbon emission intensity between steel structure and aluminum alloy structure building in the whole life cycle. This paper traces carbon emission intensity of steel and aluminum alloy and puts forward a calculation method to achieve a reasonable and localized carbon emission intensity value. At the same time, considering recycling characteristics of metal building materials, different methodologies for metal recycling in carbon accounting are studied and compared. Sensitivity analysis is conducted on three variables, which are aluminum to steel mass ratio (v), recycled content (R) and recyclability (r) using two methods for metal recycling, and different comparative results of carbon emissions in the whole life cycle of steel and aluminum structure greenhouse buildings in different scenarios are obtained. This study analyzed the impact of structural type (material) selection on carbon emissions in the whole life cycle of buildings. In addition to its findings on low-carbon advantages of steel structure greenhouses under current conditions, it also extends to dynamic research results under different scenarios in the future, which can provide reference for architects and engineers in building industry to further explore the potential of carbon reduction in the follow-up building design practice.