This example analyzes a beam that is over-reinforced by ACI standards (it cannot be considered a tension controlled section). Typically, a beam is considered over-reinforced if the steel does not yield prior to failure, but this is not allowed by ACI for flexural members. In this example, the strain in the extreme layer of tensile steel is less than 0.005, and the section cannot be considered tension controlled. The phi factor when calculating the nominal moment capacity must be adjusted accordingly.
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