Shear design and life cycle assessment of novel limestone calcined clay cement reinforced concrete beams

摘要

To reduce the impact on global warming, many countries and regions areadvocating the use of low-carbon and green supplementary cementitious materials(SCMs) to improve the cement industry. This study investigates the shearbehavior of reinforced concrete (RC) beams made with a novel green concrete,limestone, calcined clay, and cement clinker (LC~3). Full-scale shear tests wereconducted on RC and LC~3-RC beams to evaluate their fundamental behaviorfor structural applications. The shear resistance of LC~3 concrete beams wasevaluated using Chinese, American, and Eurocode codes, while carbon emissionand environmental impact were analyzed by life cycle assessment (LCA).Results showed that LC~3-RC and RC beams exhibited similar shear behaviorin terms of crack initiation, propagation, and development. The increase inconcrete strength improved the stiffness of LC~3-RC specimens, while RC specimensremained unchanged. The ductility of RC specimens was inversely proportionalto concrete strength, while LC~3-RC beams exhibited optimalductility. The increase in stirrup ratio significantly improved the shear resistanceof both LC~3-RC and RC beams. With increased shear-span ratio, the failuremode of LC~3 specimens improved, changing from diagonal-compression toshear compression or diagonal tension failure. The shear resistance of bothLC~3-RC and RC beams was underestimated by GB 50010-2010, ACI 318-19,and Eurocode 2. LC~3 concrete significantly reduced energy consumption andcarbon emissions and achieved favorable environmental benefits in terms ofGWP, PMFP, POFP, TAP, and TETP. Increasing usage of limestone in LC~3may further decrease environmental potential without sacrificing mechanicalproperties. The findings of this study contribute to the development of sustainableand environmentally friendly structures in engineering.