Did you just experience the East Coast or Colorado earthquakes? For those of us in the Northeast, this isn't something we're used to experiencing. However, out in California, it tends to be an occurrence that most likely doesn't bring as much Facebook activity as today's quakes.
Eighty percent of all earthquakes occur along the edge of the Pacific Coast. Depending on its force, some buildings, roadways or bridges could collapse.
With a daily volume of nearly 300,000 vehicles, one of the busiest bridges in the USA is the 71 year old west-coast San Francisco-Oakland Bay Bridge (SFOBB). This 4.5 mile (7.2 km) long bridge consists of two major spans. Once deemed impossible to build, Caltrans designated the SFOBB as the emergency lifeline route to use in disaster response activities. This requires the bridge to be secure, fully functional, and earthquake-resistant. In 1989, the bridge closed for more than a month due to repairs needed after the Loma Prieta earthquake. In response, the eastern span between Oakland and Yerba Buena Island is now being replaced by an entirely new crossing – making the bridge less susceptible to damage during an earthquake. This is known as the East Span Seismic Safety Project.
"We are using Instron's testing system to tensile test large diameter steel bars (#14 and #18) to ASTM A 615, ASTM A 706 and ASTM A 722 specifications," said Rosme Aguilar, the Structural Materials Testing Lab Branch Chief. "This custom built 2 million pound (8,896 kN) capacity system has replaced our existing testing system because its 1 million pound (4,448 kN) capacity could no longer handle materials of larger diameter and strength that require a higher capacity."
The system, which stands more than 26 feet (8 meters) high, is located at the Structural Materials Testing Lab in Sacramento, CA. As California's only state transportation testing lab accredited by the American Association for Laboratory Accreditation (A2LA), it quickly responded to a recent bridge collapse due to a tanker truck explosion. The lab had the responsibilities of assisting with the damage assessment to determine if the material properties of the steel girders and bent caps had been compromised due to the heat from the tanker truck fire. Remarkably, the damaged bridge was fully functional in 18 days.
Eighty percent of all earthquakes occur along the edge of the Pacific Coast. Depending on its force, some buildings, roadways or bridges could collapse.
With a daily volume of nearly 300,000 vehicles, one of the busiest bridges in the USA is the 71 year old west-coast San Francisco-Oakland Bay Bridge (SFOBB). This 4.5 mile (7.2 km) long bridge consists of two major spans. Once deemed impossible to build, Caltrans designated the SFOBB as the emergency lifeline route to use in disaster response activities. This requires the bridge to be secure, fully functional, and earthquake-resistant. In 1989, the bridge closed for more than a month due to repairs needed after the Loma Prieta earthquake. In response, the eastern span between Oakland and Yerba Buena Island is now being replaced by an entirely new crossing – making the bridge less susceptible to damage during an earthquake. This is known as the East Span Seismic Safety Project.
"We are using Instron's testing system to tensile test large diameter steel bars (#14 and #18) to ASTM A 615, ASTM A 706 and ASTM A 722 specifications," said Rosme Aguilar, the Structural Materials Testing Lab Branch Chief. "This custom built 2 million pound (8,896 kN) capacity system has replaced our existing testing system because its 1 million pound (4,448 kN) capacity could no longer handle materials of larger diameter and strength that require a higher capacity."
The system, which stands more than 26 feet (8 meters) high, is located at the Structural Materials Testing Lab in Sacramento, CA. As California's only state transportation testing lab accredited by the American Association for Laboratory Accreditation (A2LA), it quickly responded to a recent bridge collapse due to a tanker truck explosion. The lab had the responsibilities of assisting with the damage assessment to determine if the material properties of the steel girders and bent caps had been compromised due to the heat from the tanker truck fire. Remarkably, the damaged bridge was fully functional in 18 days.
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