News Detail

Adhesive Anchor Installation Certification Program

11/27/2013

In the summer of 2006, a portion of the concrete roof of the Central Artery/Tunnel Project in Boston, Mass., also known unofficially as the “Big Dig,” collapsed, killing one woman and injuring her husband. The National Transportation Safety Board (NTSB) released its accident report soon after and made recommendations to several parties, including the American Concrete Institute. The recommendation to ACI was to use its “building codes, forums, educational materials, and publications to inform design and construction agencies of the potential for gradual deformation in anchor adhesives under sustained tensile-load applications.”

ACI, in partnership with CRSI, developed the Adhesive Anchor Installation Certification Program in response to the “Big Dig” accident in Boston, MA.

As part of the overall response to the recommendations of the NTSB, ACI has partnered with CRSI to develop a certification program for Adhesive Anchor Installers. Adhesive anchors are recognized by the structural design profession as an important structural connection in many applications. Adhesive anchor effectiveness is measured by the bond strength achieved between the adhesive and concrete, and adhesive and anchor. Adhesive anchor manufacturers have developed installation procedures for their specific products that when followed, are intended to provide the proper conditions for the anchor system to achieve that required bond strength.

ACI and CRSI assembled a group of Subject Matter Experts (SMEs) who identified the criteria candidates must meet for certification as ACI/CRSI Adhesive Anchor Installers. Candidates are required to complete a certification test consisting of a 75-question written exam and a performance exam. Candidates must also be able to read, comprehend, and execute instructions to properly install adhesive anchors as are typically provided by adhesive anchor manufacturers. In addition, candidates must possess the knowledge to properly assess ambient conditions, the condition of the concrete, materials, equipment, and tools for installing adhesive anchors and determine when it is appropriate to proceed with an installation or when additional guidance from a supervisor/foreman/project engineer is needed.

One of the additional resources offered to increase awareness of adhesive anchors was a one-day in-person seminar, “Adhesive Anchors: Their Behavior and Code Design Requirements,” covered design requirements for adhesive anchors that were first introduced in the 2011 version of ACI 318, “Building Code Requirements for Structural Concrete.” The seminar discussed the material properties of common adhesives, lessons learned from failures, tension and shear failure modes, capacity reduction factors, tension and shear interaction, a qualification standard for adhesive anchors, and design of supplemental reinforcement, as well as the importance of proper anchor installation procedures in concrete.

The ACI Online Continuing Education Unit (CEU) course “Adhesive Anchors: Reliability, Environmental Exposure, and Hole Preparation” provides information on applications, systems, prequalification tests, and characteristics affecting bond strength of adhesive anchors as well as results of environmental creep behavior studies. This course, as well as the Adhesive Anchor Installation CEU course provides resources to the building community.

To learn more about ACI Certification and Education programs, visit www.concrete.org.