Title:
Elimination of Diagonal Reinforcement in Earthquake-Resistant Coupling Beams through Use of Fiber-Reinforced Concrete
Author(s):
G.J. Parra-Montesinos, J.K. Wight, C. Kopczynski, R.D. Lequesne, M. Setkit, A. Conforti, and J. Ferzli
Publication:
Symposium Paper
Volume:
313
Issue:
Appears on pages(s):
1-8
Keywords:
Coupled walls, steel fibers, link beams, shear, drift capacity INTRODUCTION
DOI:
10.14359/51689686
Date:
3/1/2017
Abstract:
The design of reinforced concrete coupling beams in regions of high seismicity typically
includes the use of diagonal bars designed to resist the entire shear demand, along with closely spaced
transverse reinforcement to provide concrete confinement and diagonal bar support. While results from
experimental investigations indicate that this design leads to stable behavior under large displacement
reversals, the required reinforcement detailing is labor intensive and time consuming. One alternative that
has been proven successful to simplify reinforcement detailing in coupling beams is the addition of
discontinuous, deformed steel fibers to the concrete. Test results indicate that elimination of diagonal
reinforcement, along with substantial reductions in confinement reinforcement over most of the beam
span, are possible in coupling beams with span-to-depth ratios greater than or equal to approximately 2.2
when a tensile strain-hardening fiber reinforced concrete is used. Given the advantages of eliminating
diagonal reinforcement in coupling beams, this new design was incorporated in high-rise structures in the
State of Washington, USA, starting in the early 2010s. In this paper, a brief summary of relevant
experimental results and the implementation of fiber reinforced concrete coupling beams in high-rise
earthquake-resistant construction is provided.