ASTM D7914/D7914M-21 PDF Download

The ASTM D7914/D7914M-21 standard is designed to determine the bend strength of FRP composite concrete reinforcements. The test is conducted by embedding the bars at a standard twelve bar diameters and measuring various data required for design purposes.

The test considers various factors that influence the tensile response of the bars, such as constituent materials, void content, volume percent reinforcement, fabrication methods, and fiber reinforcement architecture. It also takes into account factors relevant to the measured tensile response, including specimen preparation, conditioning, environment, alignment, and testing speed.

The results obtained from this test can be used for material specifications, research and development, as well as structural design and analysis. It is worth noting that while two FRP bends are tested simultaneously in this method, in some cases, only one bend may fail. In such cases, it is important to recognize that only one bend has been effectively measured, which may lead to differences in the final compiled test results compared to single FRP bend testing.

Overall, this standard provides a standardized procedure for determining the strength of FRP bent bars, which are commonly used as anchorages for stirrups in reinforced, prestressed, or post-tensioned concrete structures. The test method applies to bars with a solid cross section and involves bending the bars at a 90-degree angle. It can be conducted on standardized bars produced according to Specification D7957/D7957M or on non-standardized bars with measured and calculated cross-sectional areas as described in Test Method D7205/D7205M. The strength values obtained from this test method are short-term, quasi-static tensile strengths and do not account for sustained static or cyclic loading. If the bars are to be used under high levels of sustained or repeated loading, additional material characterization may be necessary.