Work on the Fern Hollow Bridge's replacement will progress this week when concrete is poured for the bridge pier's underground support. The old bridge, which connected Squirrel Hill to Point Breeze along Forbes Avenue, collapsed Jan. 28, injuring nine people.
Crews have spent the last few weeks boring holes for caissons in Frick Park, under the bridge. Concrete for the first caissons, which will support two sets of columns that look like double capital Ts, is set to be poured this week, according to PennDOT spokesman Steve Cowan. The new bridge will cost a maximum of $25.3 million in total.
The replacement bridge is being built under an emergency declaration that allows work to begin on the substructure while the top of the bridge is still being designed.
The general contractor, Swank Construction Co. of New Kensington, is building the new bridge from the ground up, allowing international design firm HDR to add aesthetic touches to the top part of the structure. The design team is working with elected officials and community groups to consider changes to items such as the railings and lights on the new bridge.
Due to a shortage of steel, PennDOT and HDR chose to use precast concrete I-beams for the bridge and hope to complete most of the construction this year. The final completion date will be determined by how quickly those beams are available.
When bridge construction is finished, crews will plant trees to replace any that were damaged in the accident and mitigate any other damage that occurred during construction.
The new bridge was designed with four, 10-foot-wide travel lanes; 2-foot-wide shoulders on each side; a 5-foot-wide sidewalk on the north side; and a shared path for bicyclists and runners that will be 10 feet, 5 inches wide on south side.
The National Transportation Safety Board is investigating why the old bridge, which was rated in poor condition for more than 10 years, collapsed. That review could take as long as 18 months.
Source: Pittsburgh Post-Gazette