Author Archives: CS Editor

Tilt-up projects elevated with awards

Wesley Theological Seminary (Washington, D.C.) is a four-story, thin-brick dormitory built into a hillside. Tilt-up is not common for this project type, but it provided a faster, more economical, and more durable building than traditional institutional construction methods. Photo courtesy Tilt-up Concrete Association

Wesley Theological Seminary (Washington, D.C.) is a four-story, thin-brick dormitory built into a hillside. Tilt-up is not common for this project type, but it provided a faster, more economical, and more durable building than traditional institutional construction methods. Photo courtesy Tilt-up Concrete Association

The Tilt-up Concrete Association (TCA) has announced the recipients of its annual achievement awards program, which honors projects constructed with its namesake site-cast technology.

This year, judges selected 12 overall Excellence in Achievement winners:

  • 8 West Centre (Houston, Texas) by D.E. Harvey Builders, Powers Brown Architecture, and Cardno Haynes Whaley;
  • Big Ass Fans Headquarters (Lexington, Kentucky) by Gray Construction and Kopf Consulting Group;
  • BJC at the Commons (St. Louis, Missouri) by Concrete Strategies and Forum Studio;
  • Blender Bottle (Lehi, Utah) by AE URBIA and J.M. Williams and Associates;
  • Florida Atlantic University’s 600-bed residence hall (Boca Raton, Florida) by Woodland Construction Company and Johnson Structural Group;
  • Kelsey-Seybold Clinic Corporate Offices (Pearland, Texas) by Powers Brown Architecture and Pinnacle Structural Engineers;
  • Konterra AJBP 7 (Annapolis Junction, Maryland) by Harvey-Cleary Builders, Southland Concrete, Powers Brown Architecture, and Cardno Haynes Whaley;
  • Spectrum (Middleton, Wisconsin) by Newcomb Construction Company;
  • Sugar Land Veteran’s Memorial (Sugar Land, Texas) by E.E. Reed Construction, TAS Commercial Concrete Construction, Powers Brown Architecture, Pinnacle Structural Engineers, and Big 4 Erectors;
  • Wallis State Bank I (Houston, Texas) by Arch-Con Corporation and Powers Brown Architecture;
  • Wesley Theological Seminary (Washington, D.C.) by Vantage Construction Corporation; and
  • Westgate Campus (Houston, Texas) by E.E. Reed Construction, TAS Commercial Concrete Construction, Powers Brown Architecture, and Cardno Haynes Whaley.

Additionally, TCA gave the public a chance to select the best via Facebook. Both the aforementioned Big Ass Fans building and Sugar Land Veteran’s Memorial took top spots, along with E.E. Reed’s Black Forest Ventures Jet Center/Galaxy FBO (Conroe, Texas).

For more on the individual projects, visit www.tilt-up.org/awards/tilt/2014/index.php.

 

Specifiers cautioned in use of adhesive anchors

by Gary Higbee, CSI, AIA

Contractors in Arizona participate in an American Concrete Institute-Concrete Reinforcing Steel Institute (ACI-CRSI) adhesive anchor installer certification program. Photo courtesy ACI Arizona Chapter

Contractors in Arizona participate in an American Concrete Institute-Concrete Reinforcing Steel Institute (ACI-CRSI) adhesive anchor installer certification program. Photo courtesy ACI Arizona Chapter

Designing proper construction details is an important part of architecture and engineering practice that involves more than just a grasp of building technology. If designers are not also alert to market conditions, then their details—no matter how elegant—can be ineffective and hinder the pace of a project. Overlooking the complications surrounding the specification of adhesive anchors is a prime example, as recent code changes regarding their use threaten to stall building projects in some of the United States’ largest jurisdictions.

The complications stem from the International Building Code (IBC) referencing a provision in American Concrete Institute (ACI) 318-2011, Building Code Requirements for Structural Concrete, requiring workers installing adhesive anchors in certain orientations to have ACI certification. In big construction markets poised to enact the provision, such as New York City, contractors are finding a lack of opportunities for their installers to become certified places them in an impossible position. They cannot use adhesive anchors on jobs unless their installers are certified, and if they install without certification, they risk a violation or stop work order.

How did this problem arise? It seems the only path to certification is by completing ACI/Concrete Reinforcing Steel Institute (CRSI) Adhesive Anchor Installation Certification Program—a two-day course costing from $500 to $900 per person and requiring success in both written and skills tests.

The hurdle is ACI restricts the training and testing to entities it designates. Typically, these are ACI chapters, which, in the larger construction markets are ill-equipped to handle the volume of requests. In New York City, the group tapped to provide this training (one of only three sponsoring groups throughout the state) is only able to certify 15 to 20 installers each month.

With many building trades installing adhesive anchors, this will only produce a small percentage of certified installers needed in the city for projects getting underway in 2015. Solutions such as sending installers to programs out of the city for certification are unlikely to make a dent in the need and only add to the training’s cost. Since ACI developed the certification requirement in response to the anchor failures that caused the collapse of several ceiling panels in the Boston Tunnel of Big Dig infamy, it is surprising this deficiency has not received more attention.

Impact on the industry
The bottleneck resulting from this shortage of training opportunities has the potential to interrupt construction schedules citywide. In correspondence with Louis J. Coletti, president/CEO of the Building Trades Employers Association (BTEA), the author was warned “at least 40,000 tradespersons must be certified by the effective date of the new code if we are to avoid stalling major public and private projects in the city.”

For specifiers, steering clear of adhesive anchors in favor of other types is a way to elude this glitch. However, in some applications, these products may be the preferred, or only acceptable, anchorage method because of the superior holding power in cracked or damaged concrete. Thus, it is important to clarify not all adhesive anchor installations require the installer to be certified. Only when anchors are installed in a horizontal or overhead orientation and under a sustained tension load is the ACI requirement applicable.

Due to the history of failures in these orientations, ACI requires special inspection. This adds to both the project team’s responsibilities and expenses. The architect and engineer must identify on plans filed with a building department those adhesive anchors for which special inspection is required. Subsequently, the owner must engage an independent testing laboratory to perform the inspections, which ACI 318-11 requires to be continuous—meaning no drilling and installing of adhesive anchors should occur unless an inspector is observing the installers’ procedures.

The special inspector must furnish a report to the engineer of record and to the building official affirming whether the installation procedures and materials covered by the report conform to the approved contract documents and the manufacturer’s printed installation instructions. However, before any installation is performed—and this is critical—the inspector must verify the installer’s certification. This circles back to the original problem: limited opportunities for installers to get certified.

While the designers and owners incur added costs and responsibilities, only the contractors are accountable for maintaining certified personnel to perform the installations. If construction activity is to move forward without expensive delays, these contractors must be able to find certified installers.

Until alternatives—such as moratoriums on enforcement, and permitting other qualified entities to conduct the certification training—are in place to address this looming problem, designers should be alert to the potential for added costs and delay when specifying adhesive anchors for installations requiring special inspection.

GaryHigbeeAIAGary Higbee, CSI, AIA, is the director of industry development for the Steel Institute of New York (SINY) and the Ornamental Metal Institute of New York (OMINY). Formerly the assistant director for technical services with New York State’s Building Codes Division and in architectural practice for three decades, he served in various capacities throughout this period on NYS, HUD, and ICC code drafting and development committees. Higbee is a member of the American Institute of Architects (AIA), American Institute of Steel Construction (AISC), American Society of Civil Engineers (ASCE), along with other national associations. He can be reached at higbee@siny.org.

Manufacturers provide the key to coatings specification

A professional is selecting paint for a project. Photo courtesy Sherwin-Williams

A professional is selecting paint for a project. Photo courtesy Sherwin-Williams

by Joe Kujawski

Today’s coatings are more specialized than ever, meeting the demands of various applications. It can be difficult to navigate product options, keeping in mind performance, substrate, volatile organic compound (VOC) regulations, green certifications, sustainability, and aesthetics. With so many different aspects coming into play, the process is complex.

Fortunately, manufacturers can serve as an ally to design professionals, assisting in paint and coating specifications. These companies often have an understanding of the latest industry regulations, as well as access to project history.

Effective specification despite lack of universal standards
There are numerous industry-accepted ASTM test methods used to rate coating quality, such as hide, washability, and durability. However, these are consensus-based standards developed by industry-leading organizations. To fully understand a product’s overall performance, it is vital to work with the manufacturer to specify the right product for a project. The companies can assist in determining the unique needs of a project and match them with a comprehensive set of benefits found in the right coating.

Manufacturers can also offer insight into the constantly changing VOC regulations to help specify coatings that meet current environmental standards.

Seek collaborative help
Some paint manufacturers employ trained coatings specification advisers who tap into the latest installation techniques that can be different from a national to a regional level. Organizations such as Painting and Decorating Contractors of America (PDCA) and NACE International also offer information on proper coating techniques and best practices. These organizations have hundreds of guidelines for proper touch-up practices and appropriate application methods.

In addition to application methods, green building standards and rating systems can factor into the specification process. Since there are so many different ones available, collaborating with manufacturers is key to specifying the right coatings for a project.
Leading manufacturers may provide services such as:
● custom specifications, construction document analysis, updates, and crossovers;
● reviewing submittals and substitutions; and
● supplying product and color samples.

Questions to ask
There are numerous important variables to discuss with manufacturers during the product specification process. Key questions include:
● Is this product going to withstand the project’s environmental conditions? (e.g. Is there a lot of water? Will the walls be frequently cleaned? Is it a high-traffic space? Are there temperature extremes?)
● Is the product right for the substrate or is there a special primer that needs to be specified?
● Does this coating meet VOC regulations for the area in which the project is located?
● Is it available in the color and sheen the client wants?
● Is it available in the area in which the project is located?

By taking advantage of opportunities for specifier/manufacturer collaboration, the coatings part of the construction process can be smooth and expeditious, with current, executable specifications.

Joe Kujawski HeadshotJoe Kujawski is director of marketing for the Sherwin-Williams Paint Stores Group in North America. Based out of the company’s headquarters in Cleveland, Ohio, he directs marketing strategy for the healthcare, hospitality, multi-family, and commercial architect market segments. In his career with Sherwin-Williams, Kujawski has held many field sales and marketing management positions. He holds a bachelor’s of science from Old Dominion University and an MBA from Florida Atlantic University. Kujawski can be contacted by e-mail at sherwin-williams@spongpr.com.

Field of Jeans: Maximizing visual impact with precast concrete

Levi’s Stadium in Santa Clara, California will host a wide range of events from football and soccer to motocross and concerts. The stadium is designed to be light, airy, and open. Photos courtesy Clark Pacific

by Michael Baty

Poised to serve as one of the most efficient outdoor sports and entertainment venues, Levi’s Stadium opened in Santa Clara, California, in August. Replacing the antiquated Candlestick Park, the stadium will be the new home of the San Francisco 49ers and is functionally designed for a wide range of other events including college football, soccer, motocross, and concerts.

Construction began in April 2012 for the state-of-the-art, $1.2-billion venue spanning 171,870 m2 (1.85 million sf) with seating for approximately 68,500, as well as 165 luxury suites and 8500 club seats.

Designed by HNTB Corporation (Kansas City, Missouri) and built by local firm Turner/Devcon for the Santa Clara Stadium Authority, the new stadium is designed to be light, airy, and open. The facility’s white, painted steel structure will also create a unique viewing experience for occupants. With the exposed steel, special attention was given to carefully fitting all stadium systems within the alignments of the structure to keep the aesthetic streamlined.

The precast concrete supplier for the project employed 18 million kg (40 million lb) of the material. The stadium features 2000 precast panels (e.g. risers, walls), with each ranging from 6 to 12 m (20 to 40 ft) in length and weighing up to 15,875 kg (35,000 lb)—a bit heavier than an average school bus.

To achieve the Levi’s Stadium “Field of Jeans” concrete aesthetic, a site-cast, precast, and architectural concrete release agent was required. A proprietary blend, comprising neutralized vegetable oils in mineral oil that contains no waxes, silicones, or carcinogens was used. It is solventless and non-toxic, and meets federal, Ozone Transport Commission (OTC) state, and California volatile organic compound (VOC) regulations.

The stadium features 2000 precast panels (e.g. risers, walls), with each ranging from 6 to 12 m (20 to 40 ft) in length and weighing up to 15,875 kg (35,000 lb)—a bit heavier than an average school bus.

The stadium features 2000 precast panels (e.g. risers, walls), with each ranging from 6 to 12 m (20 to 40 ft) in length and weighing up to 15,875 kg (35,000 lb)—a bit heavier than an average school bus.

Approximately 15,141 L (4000 gal) of the release agent was used in the process to provide easy and stain-free clean stripping of all the stadium’s forms and formliners from concrete. These included stadium forms for panels for the field, lower, mid, and upper levels of the stadium (single, double, and triple risers), and all vomitory wall forms—an integral part of a stadium’s viewing aesthetic. The result mimicked the form surface and site amenities with a superior finish for visually stunning concrete surfaces, without bugholes.

The release agent strips clean and promotes longer form life by keeping the form clean and accommodating easier stripping. Green technology enhancements also allow for storage of higher quantities.

The product used was installed by personnel with backpack sprayers for application to the formwork, leveraging 253 mL (0.067 gal) per minute at 40 psi.

To achieve optimal results, form surfaces had to be clean and dry before spraying. An ultra-thin, 0.01-mm (0.0005-in.) thick film was applied to get a finish that promoted easier stripping, less form cleanup, and the complete elimination of discoloration, dusting, bugholes, and concrete buildup.

After spraying in a fine mist, workers simply wiped them down evenly with a damp rag with the release agent. If puddles formed, they were wiped off.

Additionally, regular use of the release agent keeps forms clean when employed on non-porous forms and formliners made of plastic (e.g. acrylonitrile butadiene styrene [ABS] and polyvinyl chloride [PVC]), elastomeric (e.g. urethane and silicone rubber), steel, high-density plywood, and medium-density plywood overlays. It will not stain or stick from heat curing, and does not interfere with adhesion of caulk, architectural coatings, paint, sealers, and curing compounds on cured concrete surfaces.

The Levi’s Stadium construction project also boasted a unique green-focused philosophy with an eye toward sustainability as it incorporates photovoltaic (PV) panels, a vegetated roof, water-conserving plumbing systems, building control systems, and recycled materials. The stadium has achieved Leadership in Energy and Environmental Design (LEED) Gold certification, and has also been selected as the site for Super Bowl 50 in 2016.

The intent of regulating VOCs is to reduce the amount of ozone (O3) produced at ground level. From the U.S. Environmental Protection Agency’s (EPA’s) point of view, manufacturers of form release agents are responsible for meeting the VOC criteria. While the standard allowable amount of VOCs is 450 g/L (60.09 oz/gal), more stringent standards are emerging in states such as California, which requires a 250 g/L (33.38 oz/gal) standard.

1001121044Michael Baty is president of Cresset Chemical Company and has been with the company since 2000. He is a member of the National Precast Concrete Association (NPCA), National Precast/Prestressed Concrete Institute (PCI), and Precast Concrete Manufacturers’ Association of Texas (PCMA). Baty attended Bowling Green State University, majoring in computer science.

Productivity resource published

The American Society of Civil Engineers (ASCE) has released Productivity Improvement for Construction and Engineering by J.K. Yates, a book focused on implementing productivity improvement programs from engineering and construction perspectives. The text includes case studies outlining how productivity improvement programs are implemented. Contemporary approaches are summarized and readers are provided a step-by-step guide from investigation, data analysis, evaluation of alternatives, and project management. Information on building information modeling (BIM), computer simulation modeling, and sustainability concepts is also included. For more information, visit www.asce.org.