Two-Level Seismic Design Method Using Post-Yield Stiffness and Its Application to Unbonded Bar Reinforced Concrete Piers

Abstract

The two-level seismic design method using post-yield stiffness is proposed. The post-yield stiffness on the load-displacement relationship of the RC pier is found to be effective for the reduction of both the demand strength and the residual displacement under extreme earthquakes. Then, the two-level seismic design method is applied to the Unbonded Bar Reinforced Concrete (UBRC) pier that has the stable postyield stiffness. The smaller cross section is designed than the optimal cross section of the conventional RC structure. The performance of the UBRC pier is verified by the pseudodynamic tests, and as the results it is confirmed that the UBRC piers can be rationally satisfied with the required performance of the two-level seismic design.

A High Seismic Performance Concept of Integrated Bridge Pier With Triple Rc Columns Accompanied by Friction Damper Plus Gap

“…To examine structural performance, the full-scale model of the structure was simulated by numerical analysis. This study refers to the reference design of Iemura et al 21) which the designed conventional reinforced concrete structures following JRA code 3) was applied as a benchmark of the proposed structure. The bridge pier properties are 9.6 m in height, 507 tons of superstructure mass, 5.0 of the ductility factor.…”

“…The conventional RC pier was simulated to make structural performance comparisons. In this study, there are two types of conventional structures, the structure that followed the reference 21) was varied with different reinforcing steel grades, namely SD345 and USD685.…”

“…3. The structural configurations were determined with an area greater than 100% of the structure in reference 21) because, in theory, its strength is smaller than the monolith column structure, as illustrated in Fig. 4(b).…”

“…Also, it has a fairly constant resistance up to a 10.0% of drift ratio 14) . According to FEMA 356 15) , in the (a) (b) Fig.3 (a) The conventional bridge pier (with 100% cross-section area of the reference 21) ) and (b) the proposed bridge pier accompanied by FDG (with 116% cross-section area of the conventional bridge pier).…”

Study of a new type of steel slit shear wall with initially twisted links

“…Ruiz‐García and Miranda [ 2 ] found that the maximum inelastic deformation of bilinear systems with a positive second stiffness was smaller, with respect to the elastoplastic system. Iemura et al [ 3 ] found that the second stiffness of structures was effective for the reduction of both the demand of strength and the residual displacement under extreme earthquakes. Ye et al [ 4 ] studied single degree of freedom (SDOF) and multidegree of freedom (MDOF) systems to investigate the influence of second stiffness on the inelastic seismic response.…”