Apparent Bending Modulus - ASTM D747

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Used for materials too flexible to be tested according to ASTM D790 to determine relative flexibility. Test specimens are supported as a cantilevered beam and are deflected through an angle. The apparent bending modulus is calculated using the deflection angle, moment, and test specimen geometry. The calculation of the apparent bending modulus is made assuming small deflections and purely elastic specimen behavior.

Due to the nature of the test, factors influencing the apparent bending modulus (including span length, width, and specimen depth) vary during testing. Data for specimens of different thickness may not be comparable as a result.