Reinforced Concrete Link Beams

Research purpose

To develop and codify a new detailing option which aims to improve the constructability of diagonally reinforced coupling (or link) beams for tall building construction to resist earthquake loads while maintaining adequate strength and ductility. Construction of coupling beams that satisfy the strength and detailing requirements set forth in ACI 318-05 for diagonally reinforced coupling beams has proven cumbersome and costly. Test results from this project indicate that the new detailing approach provides equal if not improved behavior as compared to the alternative detailing approach; that simple modeling approaches reasonably capture measured force versus deformation behavior, and that including a reinforced and post-tensioned slab had only a modest impact on strength, stiffness, ductility, and observed damage. The outcomes of this research were incorporated in the new ACI 318-08 published in January, 2008, which reflects a remarkable project duration of only 21 months from grant award to ultimate codification.

Project Area
Structural Engineering
CPF research grant #
Award amount
Grant period
Apr 2006 - Aug 2009
Grant Status
Principal Investigator
Professor John Wallace
Industry champions

Ron Klemencic, President, Magnusson Klemencic Associates


Reinforced Concrete Link Beams: Alternative Details for Improved Construction
David Naish, John W. Wallace, J. Andrew Fry, and Ron Klemencic