Concrete inFOCUS - July/August 2010 - (Page 12)

be designed.) The foundations measured approximately 49 meters (150ft.) long and 14 meters (46ft.) wide. Four lifts completed each foundation; each lift was approximately 1.2 meters/4 feet thick. The first lift on top of the shafts was the tremie seal. CONNDOT specified the mix as Class “A” Underwater Concrete so Suzio delivered a mix containing a maximum-sized aggregate of 1¼” stone and 10% more cement due to the fact that this mix was tremied into varying depths of brackish water. This mix also contained a superplasticizer. It performed exceptionally well and proved to be the easiest to maintain, according to Dykty. The next three lifts on each foundation utilized a dynamic mix to help alleviate the possibility of thermal cracking. “The designed mix combined three mixes into one, submitted as the ‘Combined 40-50-60’,” Dykty said. “This helped the Cianbro field personnel when ordering, having just one mix instead of three. “Also, the design called for 75% slag, 25% portland cement to help maintain a lower heat of hydration. Extensive testing went into developing this mix that had to be pumped yet not exceed the allow- able slump. This window proved to be very, very tight. There was about 25mm (1 inch) of tolerance. Too tight and it would strain the concrete pump and at the upper limits of the slump range, rejection loomed. The volatility of this mix, like Ratio’s, was so sensitive to ambient temperatures and aggregate moistures that a constant vigil had to be maintained by our Quality Control Department.” To date, Suzio has produced some 25,000 cubic yards, more than 50% of the total needed. Upon completion, the 10-lane extradosed cable-stayed bridge may be the first of its kind in the United States. Extradosed bridges have structural characteristics similar to concrete box girder and cable-stayed bridges which have been successful in Europe and Japan according to CONNDOT. ■ *Special thanks for this article goes to Jim Langlois, executive director of the Connecticut Concrete Promotion Council, who first reported this story to his membership through CCPC’s newsletter. For more information, view STAY PROFITABLE GET TOUGH e rld wo leade r in concrete colorin g so dd ing valu Put more teeth into your concrete and more muscle in your profits with UltraFiber 500® – a secondary reinforcement fiber second to none. Our patented cellulose fiber delivers better finishing, unsurpassed crack reduction, and beefier bottom lines. Buckeye’s automated fiber dispenser saves you time and money on every job with precise, hassle-free fiber addition – eliminating the hidden costs and safety issues of throwing bags. And, UltraFiber 500® is the greenest fiber for concrete since it is made from cellulose, a renewable polymer, instead of petroleum-based synthetics. Finally, a ‘contractor-friendly’ fiber that is ideal for any concrete application and for any concrete finish operation which means happier customers and more fiber sales. Trust the world leader in cellulose fiber solutions – 80+ years of making a strong statement for staying tough. e to bo ss ttom lines acro the glo | 866.663.8999 JULY/AUGUST 1 12475988_Buckeye.indd 2010 ı 4/20/10 3:10:33 PM be SOLOMON COLORS, INC. Th Proud to be allied with lut i . on s, a

Table of Contents for the Digital Edition of Concrete inFOCUS - July/August 2010

Concrete inFOCUS - July/August 2010
Table of Contents
Safety First: Night Pours
What Does a Good Concrete Lab Quality Control Technician Really Need to Know? Part II
Producer Profile: Meeting the Challenge of Proper Ready Mix Design
Pervious Concrete Certification
Education Matters: Preparing to Roar Out of the Recession
In-Transit Process Control for Ready Mixed Concrete
Tech Talk: Sources of Concrete Strength Variation
Foundation Projects Strive to Increase Quality in the Concrete Industry
Environmental Scene: Green-Star and Public Outreach – What’s Involved?
Workforce Issues Q & A
Best Sellers
Who to Call
Advertisers’ Index/

Concrete inFOCUS - July/August 2010