San Francisco Bridge
Known as the San Francisco-Oakland Bridge, its construction dates back to 1937 AD with a design by the CIP team, and is considered one of the important global bridges, and it is the longest and highest bridge in the world, spanning more than thirteen square kilometers, and the bridge consists of two floors, but a devastating earthquake It hit by a magnitude of 7.1, according to the Richter scale, which was the Loma Britta earthquake. The eastern part of the bridge was completely destroyed, and the upper and lower floors collapsed. The redesign of this bridge came with the durability and toughness that it now has to avoid a devastating earthquake that may come again and hit the region after thirty years, according to what predicted by earthquake experts, and the eastern part is more specific than other parts of the bridge for safety and high efficiency.
Bridge design
The restoration process came as a design and innovation method through the construction and construction of an alternative bridge, and this new bridge is located in the northern part of the eastern extension of the bridge and separates them one hundred and fifty meters, and its parallel floors rise to about 17 meters, and it consists of 5 lanes, and passes by a railway and a pedestrian path, and a bicycle path .
The TYLin Guardian in San Francisco collaborated with Moffat and Nichol in Los Angeles to design this bridge as a joint work between them, and this collaboration came to complete the construction of the project, and until this is done successfully, it is necessary to build two steel structures temporarily in YBI, to be an alternative Temporarily twisted roads until the completion of the alternative construction, and it is indicated that the alternative construction, the eastern stretch, was built with strong and safe basic materials designed with durability to provide the necessary resistance against earthquakes and natural disasters.
Bridge components
The length of the San Francisco Bridge extends to three hundred and eighty-two meters, and its rear extension is about 180 meters. This great building is based on steel columns that number approximately four, and are connected between each other by steel shear connections, while the steel pipes used in its construction are fixed to rocks. At the edges, as far as the cables are concerned, it extends to approximately 0.78, and they have been installed on the bridge in the eastern part. In addition, a number of iron boxes, upper structures, truss beams, spirals, and eastern supports have been installed on the bridge.
Security considerations
The recommendations committee has set a number of considerations before its eyes when starting to lay the foundations of safety, which are:
- Earthquakes: Earthquakes are the first danger that threatens the bridge in the first place, but the bridge has been equipped with safety characteristics and considerations in this regard, which is the assessment of the earthquake’s effectiveness, symbolized by (FEE), and the seismic safety assessment, which is symbolized by (SEE).
- Wind: The design team resorted to a number of tests on the air tunnel in the model section to ensure a state of wind stability, and thus the wind was taken into account as a factor in the design of the range between the supports.
