On Thursday, March 30th, 2017 a section of bridge on I-85 collapsed in Atlanta, Georgia. The collapse was the result a high intensity fire underneath the bridge. A homeless man allegedly set fire to an upholstered chair, which then ignited several tons of coiled plastic conduit that had been stored underneath. What collapsed was a section of type five prestressed concrete girders produced by Garry Concrete, which was purchased by Standard Concrete Products in the late 1980’s.
The highway was fast-tracked by the Georgia DOT. It was all hands on deck. Mix approvals were sped up, materials were delivered in one or two days instead of weeks. Standard Concrete Products even started casting replacement beams within days of the collapse, and they started delivering just after two weeks. Other contractors that Standard Concrete Products worked with agreed to delay receiving their beams to make way for this important project. Another Sika Customer, Thomas Concrete, was selected to cast the columns and bridge deck.
- Quick turnaround was a huge part of the construction of this project. Georgia’s declaration of a state of emergency gave the department access to $10 million in quick-release FHWA funding.
- The total cost of the repair was projected to exceed 12 million.
- Approximately 2,100 cubic yards of high strength concrete were called for the repair. A large percentage also required design strength by the 7th day.
- Thomas Concrete used 40,000 pounds of Sika® Control® NS in the deck, a newly released product at the time of construction.
- Sika® ViscoCrete® - 2100 was also utilized to achieve the strength in less than 7 days, without the use of accelerators.
- The repair was completed in just six weeks, a full month ahead of schedule. This also meant tremendous cost savings considering the estimated USD 850,000 for each additional day that the closed bridge would have cost.