In order to maintain traffic during the replacement of the Atlantic Avenue Bridge over the Van Wyck Expressway (VWE), the bridge replacement took place in 3 stages. In each stage, a portion of the bridge would be demolished and replaced prior to the start of the subsequent stage. Detailed coordination was required to design an SOE system that avoided utilities and allowed for maintenance of traffic in along the existing bridge, the VWE, and the VWE access roads.
The Solutions Unearthed
- At the two abutments, excavation heights reached up to 28 feet. Tiebacks were not feasible due to utilities, so internal bracing was used. In order to avoid framing the new abutments around the internal bracing, the SOE design accounted for removal of the bracing after the footing was installed.
- Complicated geometry of the site and construction staging required an SOE system with an unconventional internal bracing layout and design. We performed a rigorous internal QA/QC process, since thoroughly detailed design drawings were required to ensure the design was properly conveyed to construction personnel.
- Excavations for the new foundations were deeper than the existing foundations. It was required to support the soil below the existing foundations for active portions of the existing bridge. We presented various design options and coordinated closely with the construction team to ensure all designs were constructible and cost effective.
- When changed conditions were identified by Halmar’s construction crew, GEODesign moved rapidly to perform analyses and provide revised SOE drawings.
Client: Halmar International