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1.5 LU

Tolerances are the road lines for construction—the goal is to stay within the lines, the consequences of going outside the lines depend on by how much and what is on the other side, and the lines typically do not get much attention unless there is a problem. But who defines the lines, and how were they established? What happens if the lines are not clear? Are if the car is wider than the lines? Are the lines always the same, or do they change up ahead? Like road lines for driving, tolerances are required for construction to establish appropriate expectations and reasonable bounds. This presentation will provide background on ACI 117 concrete tolerances from designer and contractor perspectives, including discussion of current tolerances, application, and common questions. The ACI 117 committee is working to update the specification document, and the presentation will provide an update on the revision, as well as other committee interests.

Michael Ahern, P.E., is a founding Principal of Pivot Engineers, which is a forensic structural engineering firm focusing on investigation, non-destructive testing, consulting, and repair and strengthening design. He works on projects across the country that range from high-rises to bridges, and include varied materials and conditions. Mr. Ahern is a professional engineer with both design and forensic experience, and is professionally active within the industry, including as Secretary of ACI Committee 117: Tolerances.

Organized by
Tuesday, 4/17
6:15pm to 8pm
Center for Architecture
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