True or False: #14 rebar is the largest diameter allowed in bundled bars in beams.

The correct choice indicates that #14 rebar is not the largest diameter permitted in bundled bars within beams. According to standard practices in reinforced concrete design, larger diameters than #14, such as #18 or #20, are allowed to be bundled, depending on the specific requirements of the project and adherence to relevant codes, such as the American Concrete Institute (ACI) guidelines. Bundling of rebar helps to increase the effective area of steel and overall structural capacity, provided that provisions for spacing, cover, and confinement are adequately followed.

Moreover, the bundling of larger rebar diameters can be advantageous for structural efficiency and reducing congestion in certain areas of the beam, allowing for tailored design approaches based on loading conditions and structural performance requirements. Other options suggest limitations that are not consistently applicable across all projects or conditions, which further confirms that #14 is not the definitive upper limit for bundled bars in structural applications.