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’re pleased to announce that our Composite Strengthening Systems (CSS) code report, ESR-3403, has been revised to recognize Simpson Strong-Tie fiber-reinforced polymers (FRP) for concrete diaphragm applications. These FRP fabrics can be used to strengthen diaphragms for in-plane shear, flexure (chords), and axial tension (collectors) to resist seismic or wind loading.
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.
Manzanita Hall is one of three remaining buildings on the University of Nevada, Reno, campus that were constructed prior to 1900. Originally named the Girls’ Cottage, Manzanita Hall was built in 1896 and was used to house 97 women in double and single rooms. Architecturally, it a created a Victorian atmosphere and offered a spacious student lounge, complete with a grand piano and a spectacular view of Manzanita Lake.
Several years ago, the hall was deemed seismically inadequate, and the electrical, plumbing and HVAC systems were likewise found to be seriously outdated and insufficient for modern college life. These structural deficiencies necessitated its closure in 2015.
Specifying our Composite Strengthening Systems™ (CSS) is unlike choosing any other product we offer. In light of the unique variables involved with selecting and using fiber-reinforced polymer (FRP) solutions, we encourage you to leverage our expertise to help with your FRP strengthening designs. To get started, we first need to determine whether FRP is right for your project. The fastest way to do that is for you to fill out our FRP Design Questionnaire. Our new Excel-based questionnaire collects your project information and helps you use the existing capacity check to evaluate whether or not FRP is suitable for your project per the requirements of ACI 562-16 Section 5.5.2. After the feasibility study, the questionnaire creates input sheets specifically for your project.
Our thoughts go out to everyone affected by Hurricane Harvey and this disaster in Texas. To help with relief efforts we are donating $50,000 to the American Red Cross Disaster Relief Fund. Employees at our Houston warehouse are safe and the employees from our McKinney branch will be doing as much as they can to help with relief efforts.
On July 25, 2017, Simpson Strong-Tie hosted the second interactive webinar in the Simpson Strong-Tie FRP Best Practices Series, “Advanced FRP Design Principles,” in which Kevin Davenport, P.E. – one of our Field Engineering Managers – and I discussed the best practices for fiber-reinforced polymer (FRP) strengthening design. The webinar examines the latest industry standards, proper use of material properties, and key governing limits when designing with FRP and discusses the assistance and support Simpson Strong-Tie Engineering Services offers from initial project assessment to installation. Watch the on-demand webinar and earn PDH and CEU credits here.Continue Reading
The wait is over. The ACI 440.2R-17 Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures is now available. The following post will highlight some of the major changes represented by this version of the document.
It’s been a long road and countless committee hours to get from the last version of ACI 440.2R-08 to this document. While there are multiple smaller changes throughout the document, the most notable update is the addition of Chapter 13 – Seismic Strengthening.
The new seismic chapter addresses the following FRP strengthening scenarios:
- Section 13.3 – Confinement with FRP
- This section includes all of the following: general considerations; plastic hinge region confinement; lap splice clamping; preventative buckling of flexural steel bars.
- Section 13.4 – Flexural Strengthening
- The flexural capacity of reinforced concrete beams and columns in expected plastic hinge regions can be enhanced using FRP only in cases where strengthening will transfer inelastic deformations from the strengthened region to other locations in the member or the structure that are able to handle the ensuing ductility demands.
- Section 13.5 – Shear Strengthening
- To enhance the seismic behavior of concrete members, FRP can be used to prevent brittle failures and promote the development of plastic hinges.
- Section 13.6 – Beam-Column Joints
- This section covers a great deal of recent research on the design and reinforcement of beam-column joints.
- Section 13.7 – Strengthening Reinforced Concrete Shear Walls
- This section provides many recommendations for FRP strengthening of R/C shear walls.
Simpson Strong-Tie Can Help
We recognize that specifying Simpson Strong-Tie® Composite Strengthening Systems™ (CSS) is unlike choosing any other product we offer. Leverage our expertise to help with your FRP strengthening designs. Our experienced technical representatives and licensed professional engineers provide complimentary design services and support – serving as your partner throughout the entire project cycle.
For complete information regarding specific products suitable to your unique situation or condition, please visit strongtie.com/css or call your local Simpson Strong-Tie RPS Specialist at (800) 999-5099.
Upcoming Free Webinar: Advanced FRP Design Principles
Join us live on July 25 for the second interactive webinar in the Simpson Strong-Tie FRP Best Practices Series: Advanced FRP Design Principles. In this webinar we will highlight some very important considerations during the FRP design processes. This will include topics such as the latest industry standards, proper use of material properties, and key governing limits when designing with FRP. Attendees will also have an opportunity to pose questions to our engineering team during the event. Continuing educations units will be offered for attending this webinar.
Learn more: Webinar – Introducing Fabric-Reinforced Cementitious Matrix (FRCM)
In this free webinar we dive into some very important considerations including the latest industry standards, material properties and key governing limits when designing with FRCM.
Continuing education credits will be offered for this webinar.
Participants can earn one professional development hour (PDH) or 0.1 continuing education unit (CEU).
The primary benefit of fiber-reinforced polymer (FRP) systems as compared with traditional retrofit methods is that significant flexural, axial or shear strength gains can be realized using an easy-to-apply composite that does not add significant weight or section to the structure. Many times it is the most economical choice given the reduced preparation and labor costs and may be installed without taking the structure out of service. However, it is important to make sure the composite is properly designed following industry standards in order to ensure that it is the right product for the application.
To provide you with a better understanding of the topic, it’s important to dispel some common myths and misconceptions that you might hear about FRP: