Simpson Strong-Tie Webcast

Structural Focus Webcast

Webcast

Fiber Reinforced Polymer (FRP) technology has been utilized for many years across various sectors, including civil engineering, aerospace and automotive industries, due to it being lightweight and versatile. FRP systems are characterized by their high strength and lightweight nature, created through the combination of fibers—typically carbon or E-glass—with a polymer matrix, often epoxy resins. The fibers serve as the principal reinforcement, while the polymer matrix acts as a binder, safeguarding the fibers and facilitating load transfer.

Recently, there has been a notable rise in the application of FRP systems for seismic and gravity strengthening of concrete and masonry structures, leading to a greater emphasis on understanding the appropriate detailing of these systems. This presentation offers an in-depth exploration of recent advancements in full-scale testing of fiber-reinforced polymer (FRP) systems under cyclic loading conditions.

This presentation aims to clarify FRP design complexities, provide insights into common failure modes, address prevalent design misconceptions, and offer recommendations for detailing of these elements based on recent and ongoing large-scale structural testing programs.

The presentation will also focus on the retrofit of the Historic Egyptian Theater. This ambitious project aimed to bring the non-ductile concrete (NDC) structure in compliance with the City of Los Angeles’ mandatory retrofit ordinance. Facing challenges posed by the rigorous retrofit requirements for Risk Category III buildings, the project leveraged the California Historical Building Code, where the ordinance’s provisions could be met.

The objective was clear: reinforce the building’s seismic resilience while preserving its historical integrity. The retrofit encompassed a strategic strengthening of diverse structural elements, including foundations, columns, beams, walls and diaphragms. Fiber-Reinforced Polymer (FRP) was selected due to its strength, lightweight properties and minimal architectural impact. FRP was seamlessly integrated with traditional strengthening solutions to achieve a well-rounded retrofit.

Noteworthy elements of the renovation included the repair of century-old concrete elements and reinforcing of the proscenium to address deteriorated connections and previously removed structural columns.

Learning Objectives:

- Understand the fundamental properties and components of Fiber Reinforced Polymer (FRP) systems and their application in seismic and gravity strengthening of concrete and masonry structures.
- Analyze common failure modes and design misconceptions associated with FRP systems, with an emphasis on detailing practices to enhance structural performance under cyclic loading.
- Evaluate the integration of FRP technology in historic building retrofits, using the Egyptian Theater project as a case study to explore strategies for balancing seismic upgrades with architectural preservation.
- Review recent and ongoing large-scale structural testing efforts, including how said efforts aim to refine and improve current FRP design guidelines and methodologies.

Speakers:

Jonathan Lehmer, S.E. Associate - Structural Focus

Jonathan Lehmer graduated with a B.S. in Architectural Engineering from Cal Poly San Luis Obispo and an M.S. in Civil Engineering from the University of Washington, Seattle. He joined Structural Focus in 2013 with a passion for historic buildings developed during study abroad programs. Jonathan is a California licensed Structural and Civil Engineer. His project experience includes historic renovations, tenant improvements, seismic upgrades and new construction projects such as the Netflix Egyptian Theater, Netflix Animation Headquarters and the Santa Monica Proper Hotel. Lehmer is an active member of SEAOSC, SEI and ACI. He enjoys learning about advanced structural engineering theories and methods.

Jose M. Duran, P.E., Strengthening Solutions Field Engineer - Simpson Strong-Tie

Jose Duran is a Strengthening Solutions Field Engineer with Simpson Strong-Tie based in San Diego. He has experience working for both material manufacturers and consulting structural design firms in California. He has retrofitted hundreds of buildings with FRP and brings a wealth of experience to projects he is involved with. He is passionate about providing cutting-edge tested solutions that improve both building performance and the built environment.