Air entrainment in concrete was discovered accidentally about 70 years ago. Since then, entrained air has provided many blessings to concrete such as increased workability at lower water-cement ratios and reduced bleeding. And there is its primary function: maximizing the resistance of hardened...
For years, paving equipment manufacturers have been telling us that stringless paving technology is close at hand. But freeing paving machines from the string lines that guide them has been much more difficult than expected. All of the paving equipment manufacturers are working hard to develop this...
The Leadership in Energy and Environmental Design (LEED) program is putting a new spin on marketing in the building design and construction industries. Through its associated Green Building Rating System, claims of environmental responsibility made by designers, builders, and owners can now be...
One of our greatest challenges as an industry is the development of our people. The issue is directly tied to employee morale, retention, and even our end-product. As such, the development of training programs that allow individuals to discover their skills and interests is crucial to creating a...
Van and Lawrence Smith founded Smith Bros. Concrete Contractors, Walden, N.Y., in 1975. They bought a truck for $300 and had to borrow $3 for gas to drive it home. For the first several years they installed block and brick masonry but gradually shifted their emphasis to poured foundations for...
Changes in concrete and construction sometimes come at a glacial pace. But such changes also tend to be significant. One such change occurred at the semi-annual ASTM meeting in June. After 8 years of development and more than 20 years of existing as a part of another standard specification, a new...
In 1999, Congress authorized the U.S. Army Corps of Engineers (COE) to design and construct modifications to the 1950s' era Folsom Dam near Sacramento, Calif., to increase the hydraulic performance of the existing outlets. A study of alternatives led the COE to decide to enlarge eight gates and add...
Every site-cast tilt-up concrete construction project requires hard work and planning before the building can be erected. Watching the enormous concrete panels being lifted and set into place is an awe-inspiring event that occurs only with careful planning, hours of training and experience, and a...
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Lightweight-aggregate, air-entrained concrete is increasingly used to cast interior, above-grade floors. There are two principal reasons for its use: cost savings and fire resistance. According to John Ries, executive director of the Expanded Shale, Clay and Slate Institute (ESCSI), Salt Lake City...
Concrete is both marvelously simple and marvelously complex. Mix appropriate amounts of portland cement, aggregates, and water, and you have one of the world's most versatile and durable construction materials. On the other hand, if you vary the proportions or the character of any of the components...
Concrete seems to be made for the desert Southwest. Add a little color to it, and it looks as if it were cut from the baked hardpan ground. Las Vegas architects and builders love concrete—its strength, its look, and its durability. To celebrate the World of Concrete's return to Vegas, here is a...
The use of brackish water in the original concrete mix has led to extensive and complex concrete repairs to Sweden's combined Svinö and Öland Bridge. Crumbling piers have been covered with reinforced concrete shells and the affected foundations strengthened. Repairs are now focusing on the deck...
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Danny Epp and his two sons, Ryan and Brandon, recently formed and poured the footings for their new home in Tsawwassen, B.C., Canada, using the Fastfoot forming membrane. The building site was excavated on two separate levels to minimize excavation costs on a steep slope. The plan was to build the...
Wal-Mart has specified Solomon Colors as a supplier for a custom liquid color for its integrally colored concrete flooring in new store installations around the country.
Kenosha, Wisconsin-based Riley Construction had several years ago purchased mast-climbing work platforms from Bracing Systems, Inc., for its masonry division.
When a new $800 diamond concrete cutting saw disappeared from a Kaikor Construction jobsite, then mysteriously reappeared 3 weeks later, not a single worker could (or would) own up to the loss. Garrett Sullivan, president of Kaikor Construction, was accustomed to losing tools as part of the cost of...