Simpson Strong-Tie, the leader in engineered structural connectors and building solutions, today joins ZFA Structural Engineers and Pullman Repair and Restoration in the launch of a new video detailing the team’s collaborative reconstruction, seismic retrofitting, and historic restoration of the Napa County Courthouse, which was critically damaged by the South Napa earthquake on April 14, 2014.

Registering 6.0 on the moment magnitude scale, the South Napa earthquake was the strongest to hit the San Francisco Bay Area since the Loma Prieta earthquake postponed the 1989 World Series. In addition to damaging plaster finishes, HVAC, and finish carpentry, the South Napa earthquake caused significant structural damage to the courthouse’s existing unreinforced masonry walls.

In the video, project leaders from Pullman and ZFA detail the use of fabric-reinforced cementitious matrix (FRCM) technology from Simpson Strong-Tie, a brand-new repair solution not used in California prior to the Napa County Courthouse restoration.

Although several construction methods were considered for the repair of the courthouse structure, concrete masonry unit (CMU) walls were rebuilt to replace the most heavily damaged masonry walls, while FRCM technology was selected instead of more traditional repointing and grout injection as the solution for the less damaged walls with their countless small cracks.

FRCM systems are currently being introduced in the structural repair and rehabilitation industry as a new, effective strengthening technology offering reduced thickness, excellent durability, superior performance in high temperatures, and ease of installation versus traditional strengthening and repair methods

“When Simpson Strong-Tie brought FRCM to our attention, our confidence in them was at a high-enough level that we felt comfortable using a product that had not been used before in California,” says ZFA Executive Principal Kevin Zucco in the video chronicling the restoration. “With Simpson Strong-Tie, we know the product support is there, we know the engineering background is there, and we know we’ll get the approvals that we need.”

To prepare the team for the first-ever application of FRCM in California, mock-ups of the courthouse walls were built at a Simpson Strong-Tie research and development facility in nearby Stockton, CA, to practice installing the FRCM system. “From design support to field support, Simpson Strong-Tie was working with us hand in hand, and that made the process smoother and easier onsite,” says Pullman Project Manager Vivek Kumar in the video.

Since FRCM systems add less weight to the structure, they provide an excellent solution for strengthening concrete and masonry substrates, particularly in seismic retrofit applications. In addition to seismic retrofits, FRCM systems are ideal for the following applications:

  • Strengthening aging, damaged, or overloaded structures
  • Repairing and strengthening surfaces in a single application
  • Correcting size and layout errors
  • Matching existing substrate finishes
  • Strengthening or repairing damp substrates, or substrates in harsh environments subject to high temperatures, humidity, abrasion, or ultraviolet (UV) radiation

To watch the Napa Courthouse restoration video, click here. For additional information on the use of FRCM in seismic retrofitting and other applications, visit the Simpson Strong-Tie FRCM information page.