As simple as ABC? Only with extensive planning and constructability review. Working for AECOM, GEODesign provided geotechnical engineering services from preliminary through final design and construction support, providing sub-surface explorations, foundation design for staged construction including temporary jump spans while keeping railroad and automobile traffic moving and providing earth support to adjacent tracks.
ENR summarized replacement of the 1896 rail bridge – “The $52.1-million bridge replacement and construction project took place in the middle of one of the busiest rail and highway corridors in the Northeast, all the while maintaining daily rail service for 125,000 commuters on 350 trains a day during the two-year project”.
The new bridge added additional travel lanes to increase road-way capacity. To speed construction, a self-propelled modular transporter installed six prefabricated bridge sections.
The Solutions Unearthed
- Subsurface investigation included borings, power soundings and horizontal abutment cores to explore old masonry block abutment geometry
- Temporary railroad track jump spans allowed construction of the abutments beneath the live rail traffic
- Drilled in Micropiles were recommended for the permanent abutments and center pier
- Driven H piles were recommended for the temporary jump spans
Client: AECOM/CONNDOT