Despite the rain and the wind, crews did manage to get one of the two hanging platforms down from the West Seattle Bridge this morning. Our photo shows the one that remains; SDOT says that one is scheduled to be brought down in the second window they have planned for this work, 7 am-11 am tomorrow. This marks the end of what SDOT calls the “emergency stabilization” work, described as follows in an update today:
Post-tensioning cables: Installed nearly 10 miles of taught steel cables inside of hollow areas of the bridge structure to strengthen and reinforce the bridge’s post-tensioning system, reducing the risk of further cracking.
Carbon-fiber wrapping: Surrounded sections of the bridge with carbon fiber-reinforced polymers to further support and strengthen the bridge. Crews performed multiple rounds of carbon-fiber wrapping and completed the final installation last week.
Pier 18 bearing release and replacement: Replaced neoprene lateral bearings which were compressed and bulging, locking together two critical parts of the bridge that typically are independent of each other. The bearings were creating additional pressure and preventing the bridge from moving as it should. Over the last few weeks, crews finished pouring and curing the concrete that will hold the new lateral bearings in place.
Next comes designing of, and hiring a contractor for, the repair plan, which SDOT says “will likely include additional post-tensioning and carbon-fiber wrapping on the center bridge span, as well as the two ‘tail spans’ on either side of the center span.”
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