ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.

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three or four spans. The girders were designed as simply supported, but additional reinforcement was provided over the piers in the bridge deck where there was no joint. Deck Used to Compare Performance of Parameters The bridge deck is 0.8 mile long, and it therefore provided a great opportunity to incorporate different experimental items to compare concrete placement methods and performance of the concrete deck. With the bridge deck separated into 13 units, each joint f o r m e d a p h y s i c a l s e p a r a t i o n i n methods for deck placement. The standard method for placing decks in Minnesota was used as the basis of the comparison, and all the other deck sections had more stringent specifications aimed at improving deck performance, durability, and quality. The variations included the wet cure time, the number and type of vibrators required for placement, reinforcing bar chair spacing, the inclusion of fibers in the concrete, and the maximum aggregate size in the concrete. Every permutation tried outside of the standard method proved to help reduce cracking. Epoxy-coated reinforcement was used in all concrete elements of the structure that were not completely under soil to increase durability and improve performance. T h e b r i d g e i s c o m p o s e d o f 4 1 spans and 40 piers. The deck area is 333,456 ft 2 and is supported by 369 precast concrete I-girders utilizing 738 bearing assemblies. The total cumulative length of concrete girders on the bridge is approximately 7.2 miles. Overall, 459 piles (408 in the open pile-bent piers and 51 supporting the abutments) were used to construct the bridge— that is the equivalent of more than 10.4 miles of piles. More than 81.5 million pounds of concrete and 2.4 million pounds of epoxy-coated reinforcement were used on the bridge. The 4225-ft length makes it the longest bridge in Minnesota using only open pile-bent piers for support. T h e n e w b r i d g e , c o m p l e t e d i n November 2015, provides a cost- effective solution to improve local and regional mobility during seasonal flooding events of the Minnesota River, which had formerly disrupted traffic in the region. ____________ Paul Gronvall is a senior engineer and Benjamin Jilk is a principal engineer a t t h e M i n n e s o t a D e p a r t m e n t o f Transportation in Oakdale, Minn. Our Products Make Your Products Better The finest quality, high strength, low absorption lightweight aggregate in the world, manufactured for use in the highest performing applications everywhere... All rocks are NOT created equal... Experience the difference STALITE Lightweight Aggregate can make... - PRECAST/PRESTRESSED CONCRETE - GEOTECHNICAL APPLICATIONS - STRUCTURAL CONCRETE - MASONRY and - ROADS Visit us at World of Concrete Booth 1670 ASPIRE Winter 2018 | 21

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