This paper describes an investigation of the use of strain-hardening, high performance fiber reinforced concrete (HPFRC) in the critical regions of coupled walls that constitute the primary lateral force resisting system of many reinforced concrete structures. The concept behind this study comes from the idea that given the advancements in fiber reinforced concreete technology, the next generation of reinforced concrete structures could utilize ductile concrete in critical regions, rather than extensive reinforcement detailing. This ductile concrete would be expected to provide shear resistance and confinement, as well as an increase in deformation capacity and energy dissipation of structural members and systems while simplifying their design and construction. It is believed that coupled structural walls, and coupling beams in particular, can significantly benefit from this design philosophy, because during a large earthquake it is anticipated that these elements will undergo significant inelastic deformations while being expected to retain a large percentage of their stiffness and dissipate a significant amount of energy.
Large-scale reversed cyclic displacement tests of individual precast coupling beam specimens were conducted to expand on previous work that investigated the potential use of HPFRC to reduce the amount and complexity of steel reinforcement currently required in coupling beams. The results of these tests, which are discussed herein, demonstrate that HPFRC can be used as a replacement for normal confinement reinforcement and can provide additional shear resistance while noticeably improving the damage tolerance of the element.
Based on the results of these component tests, a large-scale coupled wall system consisting of four precast coupling beams connecting two normally reinforced concrete structural walls was constructed and tested under displacement reversals at the University of Michigan to investigate the impact that this improved component ductility has on the system response. The design and construction of this specimen are discussed herein.
Cite this work
Researchers should cite this work as follows: