Ohio Department of transportation for the first time in their history removed and replaced an interstate bridge over the course of a weekend. Known as Accelerated Bridge Construction, two bridges were slid onto place to minimize traffic disruption. 4200 yd3 of ODOT QC2 performance based concrete was used for two bridges for both QC1 and QC2 design requirements. 50 yd3 of a rapid strength gain mix requiring 400 psi flexural in 5 hours used a low percentage of slag cement as a leveling fill material for the approach slabs to the base. The first bridge was removed and replaced on the weekend of October 16th 2015 for the south bound and placed back into service Monday October 18th, 2015. The process was repeated on the north bound lanes bridge on the weekend of December 12th 2015
Slag Cement was used for the wing walls, super structure, bridge deck and barrier walls at 25% replacement of the Portland Cement. Ohio Department of Transportation for Concrete bridge decks requires 4500 psi compressive strength and Rapid Chloride Permeability (RCP) below 1500 coulombs. Slag cement was the ideal material for high strength and lower permeability needed for durability. Concrete design for the ODOT QC2 had design strength of 5000 psi at 7 days and 6800 psi at 28 days and rcp values below 1100 coulombs. Also a low percentage of slag cement was used for rapid strength gain flowable non air concrete that had a scc spread of 30 inches and a one day design strength of 8600 psi and 28 day strength of 14000 psi.
Slag cement helped with the durability requirements for the project and the rapid strength gain mix allowed the void between the based and the bottom of the approach slabs gain strength quickly to help ensure time constrained timing of bridge being placed in use with heavy load traffic. The use of slag cement allowed for the concrete to be transported to the jobsite without slump loss or early stiffening of the concrete mix in the Ready Mix truck. The use of slag cement in the rapid strength mix allowed the Portland Cement to achieve its optimal strength gain and not “burn out” due to high Portland cement and liquid admixtures used.
Accelerated Bridge Construction (ABC), is a method that was utilized by the contractor to slide the bridge into place and is referred to as a “Slide-in” bridge or a “lateral slide”. This method is being used more frequently for the replacement of bridges with minimal traffic disruption. Removal of the old bridge and sliding in of the new bridge was done in a weekend starting Friday evening at 730 pm with the new bridge open to traffic Monday morning.
Project credits: ODOT District 2, Owner; Arcadis Design and Consultancy, Engineer; Kokosing Construction, Contractor; Palmer Bros., Concrete; Votorantim Cimentos/St. Marys cement Inc., Slag Cement