A new San Fransico - Oakland bridge is going to be the longest self stressing suspension bridge in the world. Self-stressing just means the cables aren't anchored into the banks (e.g. the Golden Gate Bridge), but instead compress the bridge deck itself. Although a more elegant design (IMHO) this is very tricky system to construct as bridge deck becomes a vital system component and needs to be in place while you run the cables.
Self Stressing on the left
The bridge also has a very innovative and cutting edge Earthquake design. One of the most devastating and unforseen problems with bridges in California was that during an Earthquake the movements of a bridges would be so great, that they would simply fall off their supports.
In order to avoid this, the brigde has large, piston like connections between segments which allow for large motions (on the order of several feet) without coming apart, while also absorbing energy. The self stressing design also helps in this regard.
Also, in its most unique Earthquake feature, the tower has a series of soft steel shear links which are meant to deform as an earthquake forces cause the tower to sway. This does two things; it absorbs energy, but it also changes the natural frequency of the structure.
Allowing the natural frequency to change during an earthquake is a very effective way of reducing the risk of collapse or serious damage, as such a structure will of its own accord settle into a response "trough" were the frequency of the earthquake and the natural frequency of the structure are "out of tune".
Most of of these design idea's have been developed and passed around in acadamia for a while now, and have been implemented in much smaller projects, but this is the first time they are to be employed in such a massive project (in this case ~$6 Billion).
Worlds Longest Self Stressing Suspension bridge.
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