Both pour lines and cold joints are common in concrete construction, but cold joints have more serious consequences. Using case histories, the authors discuss several testing methods that can be used to evaluate whether a visible pour line found on an exposed concrete surface is just a noncritical surface imperfection or a sign of a significant structural defect.
Because of finishing techniques for shotcrete construction, some tolerances must be larger than those achievable with formed construction. This allowance for increased tolerances need not diminish the serviceability, durability, or integrity of a structure. Tolerances provide an indication of the expected finished product and can identify applications where additional effort and cost may be required, or where a particular construction method may be inappropriate. Therefore, knowledge of tolerances that are consistently achievable is needed by owners and specifiers so that project requirements can be stated clearly.