Research on Seismic Performance and Damage Analysis of Reinforced ECC Composite Torsional Columns

To study the seismic performance of reinforced Engineered Cementitious Composite (ECC) columns under the combination of compression, bending, shear and torsion, quasi-static tests were conducted on 11 reinforced ECC specimens and 1 reinforcement concrete (RC) specimen to investigate the effects of axial compression ratio, torsion bending ratio, shear-span ratio, longitudinal reinforcement ratio, stirrup ratio, fiber content, raw materials and other factors on seismic performance and damage degree. The research results indicated that compared to traditional reinforced concrete, ECC specimens showed better deformation resistance and significant improvements in seismic performance and composite torsional bearing capacity; after reaching the ultimate displacement, the torque of the ECC specimen decreased smoothly, and the damage process was also relatively slow; for ECC specimens, increasing the axial compression ratio, torsion-bending ratio, shear-span ratio, and fiber content appropriately could effectively suppress the damage of components under seismic action; the reinforcement ratio had little effect on the composite torsional bearing capacity of ECC specimens, but it was necessary to configure stirrups.