Limestone calcined clay cement (LC³) is successfully used to fabricate engineered cementitious composites (ECC) exhibiting tensile strength σ_tu of 9.55 ± 0.59 MPa or tensile strain capacity ε_tu of 8.53 ± 0.30%. The high tensile strength of the composites is closely related to the improvement of fiber/matrix interfacial bond strength, and the high ductility is attributed to the enhancement of fiber dispersion homogeneity. For the case of ECC incorporating 50% LC³, the reduction of initial cracking stress σ_tc that favors the growth of the crack in a controlled manner also contributes to the improvement of strain hardening behavior. The composition analysis indicates that carboaluminates and additional hydration products including C-(A)-S-H and ettringite are generated, which contributes to the densification of the microstructure of the ECC matrix. The pore structure is thus remarkably refined. Besides, when ordinary Portland cement (OPC) is partly replaced by LC³, the consumed energy and equivalent CO₂ emission decrease, especially the equivalent CO₂ emission with the reduction ratio attaining 40.31%. It is found that ECC using 35% LC³ exhibits the highest mechanical resistance and ECC incorporating 50% LC³ shows the highest ductility from the environmental point of view.

In this study, sustainable engineered cementitious composites (ECC) exhibiting high tensile strength as well as high tensile strain capacity were successfully developed by incorporating polyethylene (PE) fiber, local recycled fine aggregate (RFA), and limestone calcined clay cement (LC³). The improvement in tensile strength and tensile ductility was attributed to the self-cementing properties of RFA as well as the pozzolanic reaction between calcined clay and cement. Carbonate aluminates were also generated owing to the reaction between calcium carbonate in limestone and the aluminates in both calcined clay and cement. The bond strength between fiber and matrix was also enhanced. At the age of 150 days, the tensile stress-strain curves of ECC containing LC³ and RFA shifted from a bilinear model to a trilinear model, and the hydrophobic PE fiber exhibited hydrophilic bonding performance when embedded in RFA-LC³-ECC matrix, which could be explained by the densified cementitious matrix as well as the refined pore structure of ECC. Moreover, the substitution of ordinary Portland cement (OPC) by LC³ resulted in energy consumption and equivalent CO₂ emission reduction ratios of 13.61% and 30.34%, respectively, when the replacement ratio of LC³ is 35%. Therefore, PE fiber-reinforced RFA-LC³-ECC demonstrates excellent mechanical performance as well as considerable environmental benefits.

In response to resource shortage and carbon dioxide emissions, an innovative type of sustainable concrete containing LC3, seawater, sea sand, and surface-treated recycled aggregates is proposed in this study to replace traditional concrete. To understand the bond properties between the sustainable concrete and CFRP bars, an investigation was conducted on the bond behavior between sand-coated CFRP bars and advanced sustainable concrete. Pull-out tests were carried out to reveal the failure mechanisms and performance of this bond behavior. The results showed that the slip increased monotonically along with the increase in confinement. The bond strength increased up to approximately 15 MPa, and the critical ratio of C/D was reached. The critical ratio approached 3.5 for the Portland cement groups, while the ratio was determined as approximately 4.5 when LC3 was introduced. When the proportion of LC3 reached 50%, there was a reduction in bond strength. A multisegmented modified bond–slip model was developed to describe the four-stage bond behavior. In terms of bond strength and slip, the proposed advanced concrete exhibited almost identical bond behavior to other types of concrete.