The Tilt-Up Concrete Association is inviting project submissions to be considered for a new Top 10 list highlighting the Most Recycled Concrete Content
The Tilt-Up Concrete Association is inviting project submissions to be considered for a new Top 10 list highlighting the Most Recycled Concrete Content on a project, coinciding with greater market interest in sustainable building solutions. The list’s inaugural project is Enterprise Park, a 440,000-sq.-ft. office development consuming 2,300 tons of recycled aggregate in concrete wall and slab mixes. The development is located at the site of Denver’s Stapleton International Airport, whose demolition has yielded 6.5 million tons of material.
Using recycled aggregates gives ready mixed suppliers greater flexibility in customizing mix designs that fulfill the needs of the project, says Jay Hock, vice president of sales and marketing for ReCrete Materials, Inc., which mixed the Enterprise Park concrete. Depending upon the recycled aggregate, you may be able to reduce your cement content and/or change the ratio of cement to fly-ash or slag. The foundation mix for the Enterprise Park project incorporated 620 tons of recycled aggregate and 115 tons of fly ash, while the tilt-up walls bear 1,570 tons of recycled aggregate.
Structures built with concrete tend to last two to three times longer than buildings constructed with other common building materials. The same qualities that make concrete a viable green material, such as thermal mass and reflectivity, also help make concrete structures sustainable by providing constant energy efficiency throughout the building’s life cycle. Recycled aggregates and supplementary cementitious materials are of great interest in the market now, says TCA Technical Director Jim Baty. Materials such as reinforcing steel bars and concrete mixtures containing fly ash, ground granulated blast-furnace slag or possibly silica fume, advance certification in a rating system like LEED, he adds, as does the use of materials that are produced within a 500-mile radius from the site.