The evaluation report, ESR-4057, was recently updated to allow the design of SET-3G adhesive for post-installed reinforcing bars using the ACI 318 development length provision. This blog has been reposted replacing SET-XP with SET-3G using the original design examples. The SET-XP evaluation report, ESR-2508, currently limits f’c to 2,500 psi for seismic applications located in seismic design category C–F. SET-3G does not carry the same limitation allowing for a considerable reduction in development length at higher values of f’c. In general, a substantially lower installation cost can be expected using SET-3G for seismic applications. Additionally, SET-3G has slightly reduced edge and spacing requirements. Engineers can access a free online calculation tool to easily determine the rebar development or lap splice length for either adhesive product.
I first learned about the application of the ACI 318 development length provision to post-installed reinforcing bars back in 2003 when I read Post-Installed Adhesive-Bonded Splices in Bridge Decks, authored by Ronald A. Cook and Scott D. Beesheim. In their series of experiments, holes were drilled adjacent to cast-in-place bars using a carbide-tipped drill bit, and new bars were secured in these holes using an anchoring adhesive presumed to be of a type commonly used in concrete construction.