ASTM Proposed Standard: Recycling of Returned Ready-Mixed Concrete

A proposed new ASTM International standard will cover the process, verification and record keeping procedures for recycling returned fresh concrete. The proposed standard, ASTM WK39876, Specification for Returned Fresh Concrete for Use in a New Batch of Ready-Mixed Concrete, is being developed by Subcommittee C09.40 on Ready-Mixed Concrete, part of ASTM International Committee C09 on Concrete and Concrete Aggregates.
 
A significant amount of concrete is returned to manufacturing plants, which can result in wasted material, the need for disposal and unnecessary environmental impact. These issues can, however, be minimized since some of the returned concrete is suitable for reuse and can be incorporated into new batches. A proposed ASTM International standard will ensure that returned fresh concrete mixed with new concrete has known and verifiable characteristics.

“Concrete is the most widely used building material in the world,” says Eric Koehler, VP, Verifi LLC, and chairman of the task group developing ASTM WK39876. “The proposed standard will help ready mixed concrete manufacturers reduce waste material and disposal requirements. Purchasers and specifiers of concrete can obtain concrete with greater recycled content while ensuring the concrete is of high quality.”

Koehler notes that technology available to facilitate the reuse of returned fresh concrete includes hydration stabilizing admixtures that can be used to extend the setting time of concrete and ensure that concrete can be used in a new batch. In addition, truck-mounted equipment can be used to measure, manage and record concrete slump, water content, temperature and load size throughout the delivery cycle to reduce the need for manual testing.

Subcommittee C09.40 welcomes all interested parties, particularly those with experience in using returned fresh concrete, to contribute to the ongoing development of ASTM WK39876.

ASTM International welcomes participation in the development of its standards. For more information on becoming an ASTM member, visit www.astm.org/JOIN.

Robert Bosch Tool, Simpson Strong-Tie Form Strategic Alliance

Robert Bosch Tool Corp., a manufacturer of professional power tools and accessories, and Simpson Strong-Tie Company Inc., a provider of concrete, masonry and anchor repair solutions, has signed an agreement to form a strategic alliance that will allow the companies to jointly pursue sales, marketing and product development opportunities in the concrete construction market.

The sales combination gives the companies’ distribution partners and customers’ access to the broadest commercial and residential product portfolio in the concrete construction industry. The strategic alliance will give distributors the opportunity to compete effectively and take market share from direct sellers.

“Both the Bosch and Simpson Strong-Tie brands are synonymous with trust, integrity and quality in the concrete and masonry markets,” says Terry Horan, president and CEO, Robert Bosch Tool Corp., North America. “This strategic alliance will leverage both companies’ engineering strengths, manufacturing practices and sales expertise to deliver anchoring and fastening solutions that meet building code requirements and improve productivity for installers.”

The alliance seeks to bring to market a complete Bosch/Simpson Strong-Tie installation system, including adhesive and mechanical anchors, as well as demolition and rotary hammers and accessories, and to improve efficiency and productivity for customers. The new venture also will provide joint jobsite training to installers and will offer distribution partners a variety of sales and marketing benefits.

“The alliance between our two companies will give our distribution partners a better way to compete against direct sellers,” says Terry Kingsfather, president, Simpson Strong-Tie. “By combining Bosch’s expertise in power tools and accessory systems with the Simpson Strong-Tie focus on providing specified, value-engineered anchoring solutions, we can drive quality business to our partners and provide customers with even better solutions.”

Lafarge Products Contribute to Kone Centre Green Design

The recently completed KONE Centre – featuring 125,000 square feet of office, restaurant and retail space – is a showcase for sustainability along the Mississippi River in Moline, Ill. The eight-story structure’s sustainable design includes 1,365 solar panels, light-harvesting technology, locally sourced recycled and renewable construction materials, and a host of energy-efficient building components. In addition, the shape of the building follows the solar axis and takes advantage of natural daylight.

A spectacular addition to the city’s riverfront when it officially opened in August, the multi-use facility was constructed with high-performance concrete containing Lafarge North America products: True Lite Lightweight Aggregate and a blended cement that included Class C fly ash and NewCem slag cement. These products, which are considered post-industrial recycled materials, made essential contributions to meeting the sustainable construction goals of the KONE Centre, which is expected to earn a LEED Gold rating from the U.S. Green Building Council.

The use of supplementary cementitious materials, such as fly ash and slag cement, as a partial replacement for portland cement can help designers and builders recycle industrial by-products, achieve higher performance from concrete mixtures, and earn points toward LEED certification of their projects. These blended cements have many properties that contribute to sustainable design - they produce stronger, longer-lasting concrete, reduce the consumption of nonrenewable raw materials, consume less energy, and turn by-products from other industries into resources that would otherwise be disposed of in landfills. Fly ash is derived from burning coal in electric utility plants, and slag cement is produced from granulated blast furnace slag, a by-product of the iron-making process.

Lafarge True Lite Lightweight Aggregate is also a recycled by-product of the iron production process.  About 35 percent lighter than most natural aggregates, this expanded slag product conforms to the U.S. and Canadian governments’ environmentally preferable purchasing programs and qualifies for points under many LEED credit categories. It offers excellent fire resistance, thermal insulating, and sound absorption capabilities and can help reduce heating and air-conditioning costs due to the capillary nature of the aggregate.

Simpson Strong-Tie Enters Concrete Repair, Protection and Strengthening Industry

Simpson Strong-Tie announces its entrance into the concrete repair, protection and strengthening business with the acquisitions of Baltimore-based Fox Industries Inc. and Switzerland-based S&P Clever Reinforcement Co.

Founded in 1969, Fox Industries manufactures a complete line of cementitious, epoxy, urethane, elastomeric and polyester coatings, grouts, mortars, adhesives, sealers, sealants, membranes and custom manufactured fiberglass parts for the marine, industrial, transportation, commercial building and public works industries. Customers interested in purchasing products from Fox should contact the inside sales team in Baltimore at 888-760-0369.

Established in 1998, S&P Clever manufactures epoxy resins and fiber-reinforced polymer (FRP) materials for concrete and asphalt reinforcement. S&P reinforcement systems are manufactured from fiber made of materials, such as carbon, glass and aramid. The company also provides static design software to engineers and planning and design offices. S&P’s manufacturing and distribution facilities are located in Switzerland, Poland, Germany, Austria, the Netherlands, Portugal and Spain.