Mode I Fracture Toughness of Tangential Moso Bamboo

This paper discusses moso bamboo (Phyllostachys pubescens) with initial crack formation by a three-point bending (SENB) method. The corrected indentation load-displacement curve (ISO 13586-2000) and the crack opening displacement in determining the crack tip extended displacement of the specimen (ASTM E399-09) were measured using a COD gauge. Then, the load-displacement curve and the value of PQ were found by the method of 95% stiffness correction. The results showed that the bamboo has good fracture toughness, and, in this experiment, the fracture results showed little difference; the result for fracture toughness can be up to 17.39 MPa •m1/2. By observing the crack under the microscope and the failure mode, it was found that the crack propagation was not established in accordance with the crack opening direction; rather it extended along the fiber interface.