Title:
Retrofit of Deficient Lap Splices Using Post-Installed Anchors
Author(s):
Katelyn S. Low, Gloriana Arrieta Martinez, David M. Wald, and Oguzhan Bayrak
Publication:
Structural Journal
Volume:
115
Issue:
6
Appears on pages(s):
1541-1550
Keywords:
lap splice; reinforced concrete; retrofit; undercut anchors
DOI:
10.14359/51702378
Date:
11/1/2018
Abstract:
As concrete infrastructure ages or is repurposed, there is an increasing need for efficient retrofit solutions. A possible retrofit technique to increase the capacity of members with deficient tension lap splices is to use post-installed, undercut anchors. The anchors can provide active confinement in the splice region. This solution requires access to only one face of the reinforced concrete element being repaired, greatly facilitating its implementation in existing structures. To evaluate this retrofit solution, four large-scale tests on beam specimens were completed at the University of Texas at Austin. One specimen contained the full tension lap splice length required by ACI 318-71 provisions and served as a control specimen. The other three specimens contained half of that tension lap splice length. One of the latter specimens was tested without a retrofit to determine baseline behavior while the other two were retrofitted. Results from these tests indicated that post-installed anchors could enhance the strength of members with deficient lap splices up to half the specified length.
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