NOVA airs episode featuring Strong Frame® Special Moment Frame Testing for NEES-Soft

SEP_3617_group_photoNOVA, the highest rated science series on television, recently aired a segment on the Colorado State University-led NEES-Soft project that tested Simpson Strong-Tie® Strong Frame® special moment frames as a seismic retrofit solution for soft-story buildings. Simpson Strong-Tie and our special moment frame were prominently featured in the clip. You can watch the entire “Making Stuff Safer” episode on PBS here.

Breaking News: Simpson Strong-Tie® Strong Frame® Special Moment Frame Testing Today

Today the NEES-Soft project has begun testing the steel Simpson Strong-Tie® Strong Frame® Special Moment Frame as a retrofit option for soft-story buildings at the NEES outdoor shake table facility at UC San Diego. The testing is focused on validating the FEMA P-807 design procedure, which attempts to create a least-cost retrofit solution by only retrofitting the garage areas of problem buildings.

NEES-Soft Building. Image credit: John W. van de Lindt.
NEES-Soft Building. Image credit: John W. van de Lindt.

Two small shakes have been run this morning on the buildings, with the expected result of zero damage. The final shake for today, though, will be a large shake (1.1 g design spectral acceleration in the short-period range). UCSD has a live video link setup at http://nees.ucsd.edu/video/. There are various camera views of the building and interior, including our frames, and should be up during the test. The update speed is not real time. We are told this last test for today will run around 1:00 pm PST, but there is always significant leeway on this.

Testing of the Simpson Strong-Tie Strong Frame Special Moment Frame.
Testing of the Simpson Strong-Tie Strong Frame Special Moment Frame. Image credit: UC San Diego video feed capture.

NEES-Soft is a project to develop and demonstrate methodologies to retrofit soft-story woof-frame buildings. The project is a collaboration of five universities and industry representatives, and will include numerical analyses and experimental testing. Full scale testing of a four-story, 1920’s-style wood building has begun at UC San Diego’s outdoor shake table facility. The testing is used to validate a FEMA P-807 design procedure, which attempts to recreate a least-cost retrofit solution by only retrofitting garage areas of the buildings.

– Paul

Soft-Story Retrofits

In February 2007 I had the opportunity to volunteer for a Soft-Story Sidewalk Survey for the San Francisco Department of Building Inspection. The purpose of the survey was to inventory buildings in San Francisco that appeared superficially to have soft or weak first stories. The volunteers were given a list of addresses to review and we recorded if the building was more than three stories tall, had five or more dwellings, and estimated what percentage of the ground level had openings in the walls. No structural analysis going on, just counting stories, mailboxes, doors and windows.

San Francisco soft-story structure. Photo credit: USGS.
San Francisco soft-story structure failure. Photo credit: USGS.
A collapsed house in San Francisco from the 1989 Loma Prieta earthquake. Photo credit: Adam Teitelbaum, AFP, Getty Images.
A collapsed soft-story in San Francisco from the 1989 Loma Prieta earthquake. Photo credit: Adam Teitelbaum, AFP, Getty Images.

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