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The combination of superelastic shape memory alloy fibers and ECC materials can form a new SMA fiber reinforced ECC composite material (SMAF-ECC) with good self-centering performance. In order to study the self-centering performance of the new composite material, 6 groups of pre-notch beam specimens were made for three-point bending cyclic loading tests, and the failure phenomenon, hysteresis curve, self-centering effect and influencing factors of the specimens were analyzed. The research results show that when the SMA fibers are effectively anchored in the ECC matrix, the SMA fibers can exert the superelastic properties to provide the ECC beams with recoverying force, and realize the crack self-closure and deflection self-recovery function for the beams, with the minimum residual crack width and deflection is only 0.9 mm and 1.3 mm respectively. Increasing fiber content can cause a small increase in the self-centering ability of the beams. However, only when the fiber diameter is appropriate, better self-centering effect can be achieved, but the difference caused by fiber diameter in the test was only 5%. SMA Fiber end forms have significant influence on self-centering performance. The knotted end beam can get a more than 70% self-centering ratio, while the straight end beams and bended end beams have no self-centering ability. The research results provide important reference for the research and application of this new self-centering materials and their structures. [ABSTRACT FROM AUTHOR]

• The self-recovery performance of SMAF-ECC under cyclic tensile loading were studied, which can provide important basis for establishing a tensile theoretical model. • SMA fibers increase the ultimate strain and ultimate tensile strength of the specimens, and significantly reduce the residual crack width and residual deformation. • The influence of SMA fiber diameter and fiber content to the self-recovery performance of the specimens was studied and analyzed. • The stress state of SMA fibers during the loading process was investigated, providing a basis for evaluating the performance of SMA superelasticity. The incorporation of superelastic shape memory alloy (SMA) fibers into engineered cementitious composites (ECC) has led to a novel composite material, SMAF-ECC, which possesses excellent deformation, energy dissipation, and self-recovery capabilities. To understand the self-recovery performance of this new composite material under tensile loading, this study conducted uniaxial cyclic tension tests on SMAF-ECC specimens to investigate stress, strain, crack width, strain recovery rate, and crack recovery rate, while also considering the primary influencing factors such as SMA fiber diameter and content. The results indicate that the addition of SMA fibers improves the ultimate strain and ultimate tensile strength of ECC; increasing fiber content effectively enhances the strain and crack recovery rates of SMAF-ECC specimens, with the maximum strain recovery rate and crack recovery rate of the tested specimens reaching 69% and 77%, respectively. Both too large and too small SMA fiber diameters lead to reduced recovery rates. In this experiment, when the fiber diameter was 0.5 mm, the strain and crack recovery rates of the specimens were the highest, with a crack recovery rate of 53%, approximately 1.7 times that of specimens with 1 mm and 0.2 mm diameter SMA fibers. These findings provide a reliable basis for establishing a theoretical model of the tensile mechanical properties of SMAF-ECC composite materials. [ABSTRACT FROM AUTHOR]