• The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal


Title: Large Reinforced Concrete Special Moment Frame Beams under Simulated Seismic Loading

Author(s): Tea Visnjic, Grigorios Antonellis, Marios Panagiotou, and Jack P. Moehle

Publication: Structural Journal

Volume: 113

Issue: 3

Appears on pages(s): 469-480

Keywords: beams; cyclic; frames; reinforced concrete; reinforcement buckling; seismic

DOI: 10.14359/51688193

Date: 5/1/2016

In modern construction of tall reinforced concrete special moment-resisting frames, beams with section depth reaching 1200 mm (48 in.) are not uncommon. The ACI 318-08 Code provisions for these beams could result in hoop spacing as large as 300 mm (12 in.) in the plastic hinge zone, potentially leading to inferior beam performance during earthquakes due to premature buckling of the longitudinal reinforcement. An experimental study investigated the seismic behavior of two 1220 mm (48 in.) deep special moment frame beams, one barely satisfying the ACI 318-08 hoop spacing limits and another with closer hoop spacing. The predominant failure mode of both specimens was longitudinal bar buckling; however, behavior was notably improved in the beam with reduced hoop spacing. The tests served as the basis for building code changes introduced in ACI 318-11.