The flexural testing methods for advanced composite materials have not yet been authorized internationally. In the present paper, the effects of various factors such as loading mode, span length, specimen size, radius of loading nose and control mode of loading etc. on the static and fatigue flexural properties were discussed in the experiments under the 3-point, 4-point bendings and pure bending. The specimens were the unidirectional carbon-fiber-reinforced plastics and the failures took place beneath the loading noses due to stress concentration in both 3-point and 4-point bending methods and the finite element method analysis were performed in order to explain the experimental results. Accordingly, it was found that the pure bending testing method is the best and the 3-point and 4-point methods are not recommended. If the experi-ment in 3-point or 4-point bending is inevitably performed, a film should be inserted beneath a loading nose which gives the reasonable strength by alleviating the stress concentration.
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