Study on the Seismic Performance of Steel-Engineered Cementitious Composites Columns with Ties

To simplify the construction of steel-reinforced concrete structures while maintaining structural performance, this paper proposes a new type of tied steel–ECC composite structure with tie bars. The reinforcement cage is eliminated to improve constructability, ECC material is used to replace concrete, and tie bars are set between the steel flanges to maintain structural performance. Through a quasi-static test comparison of specimens with and without tie bars, it was found that the cumulative energy dissipation of the specimen with tie bars increased by 13.7%. The column foot exhibited flexural failure without ECC spalling, demonstrating excellent ductility and seismic performance. Finite element analysis indicates that the tie bars effectively suppress flange buckling and enhance core area confinement. Parameter variation analysis via finite element modeling shows that an increase in the axial load ratio reduces bearing capacity and energy dissipation. When the axial load ratio increases from 0.1 to 0.4, the bearing capacity decreases by 3.6%, and ductility decreases by 40.2%. The strength of the tie bars has a minimal impact on seismic performance. Reducing the tie bar spacing significantly improves bearing capacity and energy dissipation capacity. When the tie bar spacing is reduced from 200mm to 50mm, the bearing capacity increases by 10.7%. The steel–ECC composite structure with tie bars can maintain good seismic performance while simplifying construction.