Project Profile: Reinforcing Concrete Joists to Increase Load Rating

We’re excited to share another fiber-reinforced polymer (FRP) project that required both flexural and shear strengthening (photo below) of reinforced concrete joists to enable the slab floors to carry more live load. The structure is in Southern California, and appears to have been built in the 1950s or 1960s when pan joist construction was common. The EOR for this project, Structural Focus, is an experienced structural engineering firm known for seismic retrofit solutions. The FRP applicator was FD Thomas Structural Specialties, a contractor with decades of FRP installation experience.

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Reasons to Specify SET-3G Adhesive for Anchorage in Concrete Construction

Weve been receiving a lot of requests lately from engineers wanting to know exactly what the difference is between Simpson Strong-Tie’s relatively new adhesive, SET-3G, and its predecessor, SET-XP®. Both are epoxy-based adhesives used to anchor threaded rods and reinforcing bars in concrete base material for structural applicationsIf you perform a live pull test on a ½“-diameter mild steel rod embedded 4 deep in 3,000 psi uncracked normal-weight concrete, the result will likely be the samein both cases, the steel rod will break in a ductile manner at around 11 kips. You can see this hourglass-shaped steel failure mode happening in Figure 1. (To learn more about anchorage failure modes and ductility, check out this blog). Yet, the SET-3G design values shown in ESR-4057 come out ahead. But why? 

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