A PROPOSAL OF ESTIMATION METHOD FOR CRACK INITIATION BY TWO TYPE TESTS

A discussion about evaluation method of mode I fracture toughness performance with wood for structural glulam Part 3

Abstract

In this paper we conducted three-point bending type(3PB) test to evaluate fracture toughness of woods. On the previous paper, we defined crack initiation point on the load-deflection curve and identified three fracture features. Then we set 3PB specimens failed in ductile fracture based on those results. As a result, we observed the same fracture features on 3PB test. Additionally, the specimens were analyzed with FEM methods and the formula on JSME is useful for calculation mode I fracture toughness for crack initiation. With a comparison of CT and 3PB tests, we can evaluate fracture toughness for crack initiation by these test methods under the condition defined this paper.