High-Strength Steel Bars in Reinforced Concrete Walls: Influence of Mechanical Properties of Steel on Deformation Capacity
University of Kansas
December 2014 - December 2016
Andres Lepage, Ph.D.
Ramon Gilsanz – Gilsanz Murray Steficek
Dave Fields – MKA
Dominic Kelly – SGH
Conrad Paulson – WJE
American Concrete Institute (ACI), Concrete Reinforcing Steel Institute (CRSI)
A study of the effects of uniform elongation and ft/fy on the deformation capacity of unsymmetrical walls has been identified by members of ATC 115 as a high-priority item. Results from this study will provide a basis for defining acceptable mechanical properties in specifications of high-strength steel reinforcing bars. Because of their geometry, tests of flanged walls are critical for evaluating the reinforcement strain capacity needed to ensure that earthquake-resistant structures have acceptable drift capacity. The primary aim of this study is to determine the minimum uniform elongation required of high-strength reinforcing bars used in seismic applications. The study will also examine whether ft/fy impacts the required minimum uniform elongation by altering the spread of plasticity in the vicinity of the wall-yielding region.