East Robinson Street Bridge Shoring
The New York State Department of Transportation (DOT) designed a new three-span bridge for East Robinson Street over Tonawanda Creek. Pier 1 is located in Tonawanda Creek. Construction of a cofferdam was required for construction of Pier 1, which is supported by end-bearing H-piles. A cofferdam was also required for the demolition of the existing pier.
McMahon & Mann Consulting Engineers, P.C. designed the excavation support system such that the sheet piles avoided the battered piles supporting the existing pier and the batter piles scheduled for the new pier. The support system design also considered the unbalanced pressures created by the different ground surface elevations on opposite sides of the cofferdam and the lower water pressure inside the cofferdam.
The sheet piles also needed to address seepage beneath the tips so that the contractor could dewater the excavation to allow for pile driving and concrete placement for the pier in a dry condition.