News Detail

ACI’s Spring Convention Hosts Slag Cement Association Project Awards

4/19/2016

The American Concrete Institute’s (ACI) Concrete Convention & Exposition provides its members and concrete industry professionals an avenue to meet with committees, make important decisions, learn about industry updates during technical sessions, and network with peers.  This year’s spring convention in Milwaukee, WI also played host to the Slag Cement Association (SCA) 2015 Project of the Year Awards.

The ceremony took place on Monday, April 18, 2016 during a two-part technical session titled “Slag Cement Use in Notable Structures,” sponsored by ACI Committee 233: Ground Slag in Concrete.  The session speakers demonstrated that slag cement is used across North America in high-profile projects, and featured a variety of examples of slag cement applications to achieve combinations of low-heat, high-heat, high-strength, increased workability, low permeability, low unit-weight, whiter color, and higher recycled materials content.

The awards were presented during the afternoon session.  Projects were selected for excellence and innovation in concrete using slag cement. Award categories included architectural design, concrete durability, green design, high performance, and sustainability.  John Melandar of the SCA led the awards presentation, and Peter Bohme of LafargeHolcim presented each winner with their award.

Two winners were selected in the architectural category:  Children’s Hospital at VCU and Jade Signature. The 640,000 square-foot outpatient Children’s pavilion features naturalistic elements of light and green space to create an oasis for children, and slag cement used 60% replacement for mass concrete for mat foundation and 40% for structural light weight and 5000-psi concrete.  The Jade Signature “tower on the beach” is designed to maximize sun exposure and provide an inspiring connection to sea and sky.  Slag cement was used in the deep-soil mixing process at 80-90% of a cement slurry to stabilize soil, and 60% slag cement was used in 10,000 psi mass concrete for the mat foundation.

Next, two projects were also awarded for durability:  Arlington River Bridge on University Boulevard, and the City of Clyde Waste Water Treatment Plant Equalization Basin Project.  A new two-lane concrete bridge replaced an aging structure over the Arlington River.  Slag cement was used at 60% with 10% fly ash in ternary concrete mixture to enhance sustainability and durability in salt water environment, and the lighter color will improve nighttime visibility.  A one-million gallon flow equalization basin was created to meet Ohio EPA requirements.  Use of slag cement provided desired sulfate resistance, reduced permeability, and reduced susceptibility to alkali silica reaction in this aggressive waste water treatment environment.

The green design category winners were Heritage Cooperative Agricultural Campus and Research Facility Tilikum Crossing Bridge.  Concrete mixture containing slag cement provided consistent slump, air content, set time, and strength gain, and slag cement reduced the environmental footprint of the concrete mixture in the agricultural campus.  The 1700-ft cable-stayed bridge used slag cement in high performance concrete specified to provide 3500 psi at 18 hours and 8000 psi in 56 days.  Use of slag cement reduced the carbon footprint, contributing to achieving green-design objectives of the Portland community.

432 Park Avenue, New York, NY, won the high performance award.  At 1,396 feet, this structure is the tallest residential building in the Western Hemisphere. 

The innovative applications award was presented to the I-79/I-70 South Junction, Washington, PA for an innovative box-culvert re-design eliminating the need for crossovers during the rehabilitation of two mainline I-70 bridges.  Slag cement was used at 50% replacement in both self-consolidating concrete and mass concrete mixtures.

The reconstruction of the JFK International Airport – Runway 4L-22R was given the sustainability award.  Workers rehabilitated existing asphalt runway with 18-in concrete pavement overlay, and extended it by 700 ft and widened by 50 ft.  ASTM C595 Type IS (40) slag blended cement in 4-aggregate mixture provided constructability, strength, durability, and smoothness at a reduced environmental impact.

More information on each project, including photos, slag cement supplies, and other contributors, will be available soon in Concrete International and on the SCA website.