San Francisco in San Francisco City and County, California — The American West (Pacific Coastal)
Resisting the Twisting
A storm on December 1, 1951, caused the Golden Gate Bridge to twist and vibrate enough to cause some minor damage, so the Bridge was retrofitted from 1953 to 1954. The retrofit added new bracing across the bottom, connecting the two steel trusses that support the roadway deck. This change increased the Bridge's twisting, or torsional, stiffness.
Twist each of these models to feel which one is stiffer
Original Bridge Deck Shape
This is a scale model of a 500-foot (152-meter) length of the Golden Gate Bridge, without the roadway on top. The trusses on the sides, along with the framing on top that supports the roadway, form an upside-down U-shape.
Retrofitted Bridge Deck Shape
This model shows the Bridge deck today. The difference from the original design, at left, is the addition of bottom bracing. The cross section is a closed shape.
Location. 37° Touch for map. Marker is located along the Battery East trail, about 1/10 mile west of the Battery East parking lot. Marker is in this post office area: San Francisco CA 94129, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within walking distance of this marker. The Era of Earthworks Batteries (a few steps from this marker); Fort Point National Historic Site (about 700 feet away, measured in a direct line); The Golden Gate Bridge: Vision, Genius and Expert Care (about 700 feet away); Fort Point (approx. 0.2 miles away); Crissy Field (approx. 0.2 miles away); Setting A Deadly Obstacle Course (approx. 0.2 miles away); Men of Vision (approx. 0.2 miles away); Castillo de San Joaquin (approx. 0.2 miles away). Touch for a list and map of all markers in San Francisco.
Also see . . .
1. Sausalito News, Volume 66, Number 48, 6 December 1951. The Golden Gate Bridge, which was closed to traffic from 5:55 p.m. to 8:54 p.m. during last Saturday night’s gale was primarily a precautionary measure, according to the bridge's general manager. The bridge could have been reopened a half hour later, but remained closed to permit time for an inspection. Except for World War II blackouts, the shutdown marked the first in the 14-year (Submitted on March 18, 2019, by Cosmos Mariner of Cape Canaveral, Florida.)
2. Golden Gate Bridge Deck Vibration, Stability, and Retrofit. Princeton University civil engineering professor Dr. Maria Garlock shows how this exhibit, designed by Elizabeth Deir, a student of hers, lets the visitor feel the difference in the torsional (twisting) stiffness of the original Bridge deck as compared to the deck after its wind engineering retrofit was implemented in the 1950s. (Submitted on March 18, 2019, by Cosmos Mariner of Cape Canaveral, Florida.)
Categories. • Architecture • Bridges & Viaducts • Man-Made Features •
Credits. This page was last revised on March 18, 2019. This page originally submitted on March 17, 2019, by Cosmos Mariner of Cape Canaveral, Florida. This page has been viewed 41 times since then. Photos: 1, 2, 3. submitted on March 18, 2019, by Cosmos Mariner of Cape Canaveral, Florida.