Columbia, MO Project:
Emery Sapp & Sons of Columbia, Missouri, completed a Design Build bridge project on I-70 in Columbia utilizing some very unique design and construction concepts that delivered new bridges in a fast track manner while minimizing disruption to the traveling public. One unique aspect of this project was a Slide In Bridge Construction (SBIC) where one of the new bridges was constructed next to the existing bridge and then slid into place when completed. To complete the Slide In Bridge it was necessary to utilize a rapid strength concrete for the bridge approach closure pours so that the new bridge could be opened to traffic quickly.
Emery Sapp & Sons chose to utilize the FasTrac 246 Concrete product and the FasTrac Concrete Mixer in order to complete the closure pours. The FasTrac 246 Concrete was delivered to the project in ½ cubic yard super sacks allowing for efficient mixing of the 9 cubic yards needed to complete the closure pours. The FasTrac Concrete provided 4000 PSI concrete in 3 hours enabling the bridge to opened to traffic the same day.
Independence, MO Project:
State Route 291 at 23rd St. in Independence, MO is a heavily traveled intersection that is also a truck route servicing heavy industry in the Kansas City area. Average daily traffic at this intersection is approximately 27,000 vehicles with 10% truck traffic. As is common at intersections, the asphalt pavement tends to rut and shove and in 2001 the Missouri DOT decided to try a thin 4” concrete overlay in order to get longer life out of the pavement. Fast forward to 2016 and the thin concrete overlay performed very well giving the intersection three times the life of the previous asphalt overlays, however some of the concrete overlay panels were starting to show their age and in need of repair or replacement. MODOT decided to replace a number of worn out areas, but given the high traffic count in this busy intersection there was a need to take a “Fast Track” approach to the reconstruction. FasTrac 300 Cement was chosen as a means to complete the concrete paving repair and allow for very fast return to traffic in order to minimize disruption to the traveling public and local businesses.
Lane closures began at 7:00 p.m. on Friday evening and a milling operation commenced to mill out the damaged areas. Given the thick underlying asphalt pavement and concern over potentially poor asphalt just under the 4” concrete layer, the decision was made to mill out to an average depth of 9”. Contractor, Realm Construction, started placing the FasTrac Concrete at 7:30 a.m. on Saturday morning, November 5, 2016. There was a total of ten slabs replaced ranging from just under one cubic yard to just over thirteen cubic yards. Three volumetric mixers were utilized as the location did not allow for material re-load and the mixers were reloaded at a site 15 minutes away from the pour site. A total of forty cubic yards of FasTrac Concrete was placed and finished in just under four hours. The concrete reached in excess of 4200 PSI compressive strength in 2.5 hours and in excess of 4500 PSI in 3 hours – outstanding performance given the cool 50 degree temperatures and placement slump of 8”-9”.
The FasTrac 300 Cement allowed the intersection to be totally reopened to traffic by early afternoon and is expected to provide long service life as the product contains zero chlorides and the low water/cement ratio of .36 afforded by the cement provides obvious long term quality benefits in reduced permeability and extremely low shrinkage.