000019106 001__ 19106
000019106 005__ 20170118182259.0
000019106 04107 $$aeng
000019106 046__ $$k2017-01-09
000019106 100__ $$aChoi, Young-Jae
000019106 24500 $$aAn Innovative and Simplistic Reinforcement Detail for Reinforced Concrete Coupling Beams

000019106 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000019106 260__ $$b
000019106 506__ $$arestricted
000019106 520__ $$2eng$$aDiagonally reinforced coupling beams (DCBs) are commonly used as seismic-force resisting members for medium- to high-rise buildings in high seismic zones. The diagonal reinforcing bars in DCBs are most effective when the beam has a span-to-depth ratio less than 2. However, modern construction typically requires span-todepth ratios between 2.4 to 4, which leads to a very shallow angle of inclination for the diagonal reinforcement. The lower angles of inclination, when combined with the detailing requirements specified in ACI 318, result in reinforcement congestion and construction difficulties. These issues can be considerably minimized by utilizing an innovative and simplistic reinforcing scheme consisting of two separate cages similar to those used for typical beams in reinforced concrete special moment frames. The proposed coupling beam has high stiffness and acts like a conventional coupling beam under small displacements. When large displacements occur, cracks begin developing at the beam’s mid-span and mid-height area where the narrow unreinforced concrete strip is located, gradually propagating towards the beam’s ends. The cracks eventually separate the coupling beam into two slender beams where each has nearly twice the aspect ratio of the original coupling beam. This split essentially transforms the shear-dominated deep beam behavior into a flexure-dominated slender beam behavior. Because damage initiates from the center of the beam and then spreads towards the ends, the beam’s ends maintain their integrity even under very large displacements thereby eliminating the sliding shear failure at the beam-to-wall interface. Testing results on half-scale specimens with span-to-depth ratios of 2.4 and 3.3 showed that the proposed coupling beam not only has high ductility and shear strength, but can significantly reduce construction issues in conventional DCBs. In addition, because the cracks always initiate at mid-span and mid-height, the damage location can be easily predicted, which makes repair work easier after moderate earthquakes.

000019106 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000019106 653__ $$aRC coupling beam, diagonally reinforced coupling beam, double-beam coupling beam, span-to-depth ratio

000019106 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000019106 720__ $$aChoi, Young-Jae$$iHajyalikhani, Poorya$$iChao, Shih-Ho
000019106 8560_ $$ffischerc@itam.cas.cz
000019106 8564_ $$s2123726$$uhttps://invenio.itam.cas.cz/record/19106/files/2859.pdf$$yOriginal version of the author's contribution as presented on USB, paper 2859.
000019106 962__ $$r16048
000019106 980__ $$aPAPER