Structural renovation work continues on an historic, 1920s-era theater in Hollywood, California. This major renovation will improve the structural performance of the building and help ensure that theatergoers and building occupants are safe in the event of a major earthquake. We are excited to share a second update on this project that focuses on the use of fiber-reinforced polymer (FRP) for strengthening the theater’s roof diaphragm. Continue Reading
Structural renovation work continues on a historic, 1920s-era building in Hollywood, California. This major renovation will improve the structural performance of the building and help ensure that theatregoers and other occupants are safe in the event of a major earthquake.
Not all post-installed mechanical anchors are created equal. There are key differences between screw and expansion anchor types — differences that include how they gain their holding strength, installation requirements, and overall anchor performance. In the following post, field engineers Todd Hamilton, Chris Johnson and Derek Gilbert compare the two anchor types.
Simpson Strong-Tie and Structural Technologies formed a strategic alliance for Composite Strengthening Systems™ (CSS) products in 2021. CSS products include fiber-reinforced polymer (FRP) and fabric-reinforced cementitious matrix (FRCM) strengthening systems. Additionally, where CSS products are not a viable solution, the alliance can also offer recommendations and design for other non-CSS or conventional strengthening solutions. This alliance allows each firm to specialize in their areas of expertise:
Did you know that Simpson Strong-Tie offers free education and training to the structural engineering and building industries? On May 18, 2022, a team of Simpson engineers and technical sales reps, in conjunction with Structural Technologies, hosted a workshop in Portland on fiber-reinforced polymer (FRP) and fabric-reinforced cementitious matrix (FRCM) seismic strengthening solutions for concrete, reinforced masonry and unreinforced masonry structures. The workshop educated engineers on how Composite Strengthening Systems™ (our FRP and FRCM solutions) can be used to strengthen structural concrete and masonry elements in their projects. This was our first workshop event since COVID restrictions were placed, and we were excited to host the industry again.
In the last few years, Simpson Strong-Tie has heard from a number of structural engineers expressing frustration with the lack of performance data for shallowly embedded, post-installed anchors (shallow anchors). Engineers of Record (EOR) have identified a common application for shallow anchors as those related to attachment of sill plates for structural and nonstructural wall-to-podium slab connections. One dilemma faced by the EORs originates in their desire to prevent damage to concrete podium slab reinforcement, especially where reinforcement is located close to the slab’s top surface to resist negative bending moments. EORs further indicate that shallow anchors are frequently needed for the following attachments: hanging MEP fixtures; attaching nonstructural components associated with tenant improvements; and anchoring light equipment.
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.
We’ve 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 applications. If 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 same; in 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?
At Simpson Strong-Tie, we’re always seeking out new opportunities for innovation while helping customers find solutions to new challenges. In fact, “relentless customer focus” and “risk-taking innovation” are two of our nine company values. These two values recently came into play with a challenge to test our Composite Strengthening Systems™ FRP products in a new application on a 17-foot-tall concrete column.
The Simpson Strong-Tie® Composite Strengthening Systems™ was used to restore and strengthen 6 distressed cast-in-place concrete grain silos with a combination of carbon and glass FRP, meeting a tight timeline and budget.