The New York Times ran a fascinating feature this week on the design elements that will allow the new eastern span of the Bay Bridge to essentially 'go with the flow' in a major earthquake. Be sure to check out the wonderful interactive feature accompanying the article.
Henry Fountain reports on the bridge's unique design features:
"That design includes a 525-foot-tall suspension bridge tower made up of four steel shafts that should sway in a major earthquake, up to about five feet at the top. But the brunt of the force would be absorbed by connecting plates between the shafts, called shear links.
The bridge's concrete piers are designed to sway as well, limiting damage to areas with extra steel reinforcing. And at joints along the entire span there are 60-foot sliding steel tubes, called hinge pipe beams, with sacrificial sections of weaker steel that should help spare the rest of the structure as it moves in a quake."