Seismic Behavior of a Coupled Wall System with HPFRC Materials in Critical Regions

Abstract

High-performance fiber-reinforced concrete (HPFRC) materials have a unique strain-hardening behavior in tension that translates into enhanced structural response, especially under reversed cyclic loading. Recent experimental research has shown that the use of HPFRC to replace regular concrete in components subjected to high cyclic deformation demands can lead to significant benefits, such as relaxation of detailing requirements and reduction in the amount of reinforcing steel. A structural system that is a good candidate to benefit from HPFRC is reinforced concrete coupled walls, where coupling beams and plastic hinge zones undergo large cyclic deformation demands during the design seismic event. This paper discusses the seismic performance of a prototype 18-story coupled-wall system in which the wall plastic hinge zones and the coupling beams are made of HPFRC materials instead of regular reinforced concrete. Computational simulation models are used to investigate system performance under various hazard levels, and system response is evaluated through various parameters including interstory drift, rotation, and distortion of critical structural parts. The simulation results show that the use of HPFRC in place of regular concrete leads to good overall seismic response with enhanced plastic hinging behavior in the wall piers and crack control in the coupling beams and piers.