Seismic Performance of Exterior Steel Ring-Stiffener Joint

Abstract

We study the seismic performance of the exterior steel ring-stiffener (ESRS) joint, a member that is used to connect a steel beam to a square steel tubular column filled with steel fibre recycled concrete for seismic resistance. To this end, the influence of seismic factors such as axial compression ratio and beam-column linear stiffness ratio on seven specimens is studied. A physical test is conducted on the specimens with a series of cyclic loadings. The testing and analysis of hysteretic loops and skeleton curves of the ESRS joints revealed the seismic performance characteristics including failure mode, rigidity, ductility, bearing-capacity degradation, and energy dissipation capacity. The results reveal (a) damage to the specimens at the beam-end near the joint, (b) no failure at the joints’ core area and column, (c) appearance of a plastic hinge at the beam-end near the joint, and (d) plump spindle-shaped hysteretic loops and normal rigidity degradation curves in the specimens. The specimens are then simulated with the finite element method (FEM) and the results are compared with those of the physical test.

Numerical Simulation Analysis of the Seismic Performance of Precast Bridge Piers

“…e seismic performance of the component in the test was evaluated using the rebar strain ε s , drift ratio DR, displacement ductility factor of the component μ Δ , residual deformation index RDI, equivalent viscous damping ratio ξ eq , and normalized equivalent sti ness n k . ε s was measured by strain gauges; DR is de ned as the ratio of the horizontal control displacement of the specimen at each loading level to the e ective loading height of the specimen; and μ Δ is de ned as the ratio of the lateral displacement at a given loading level to the idealized yield displacement, as illustrated in Figure 4 [17].…”

“…n k is de ned as the ratio of the equivalent sti ness K eff to the initial sti ness K 0 , where K eff is the slope of the equivalent linear elastic system, that is, the ratio of the horizontal force to the lateral displacement of the specimen at a given loading level. e calculation of the RDI, ξ eq , and n k is illustrated in Figure 5 [17].…”