Wilmington, Del. — The job of building eight temporary towers beneath the I-495 southbound bridge deck and preparing them for the jacking operation is continuing. The positions on the top of the towers where the jacks will interact with the deck must be exact and are critical to the success of the project. This requires the bridge engineers to design and the contractor to fabricate and install a jacking system consisting of header beams, special housing boxes to hold the jacks, bracing, and many other custom steel components. That work is going on now.
Various other tasks are also being done this week, including curing of the concrete pours around the base of the pier closest to the Christina River, closing the holes that were made in the bridge deck to allow steel to pass through it, and strengthening the jacking towers by tethering them to anchor points with steel cables.
Once these construction activities are done, the jacks can be put in place to begin the slow process of realigning the bridge deck. How well this phase of the work will go is unknown, and the possibility does exist for setbacks or problems to occur, DelDOT cautions.
I-495 northbound bridge work continues with grade beams and underpinning activities underway at all four piers.