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At the connections in timber structures loaded perpendicular to grain, the wood
sometimes fractures in brittle or ductile. To this problem, some researchers
conducted some type tests, and analyzed. But there isn’t a standard evaluation
method. Additionally someone used very clear wood, so the dates for the general
wood for the timber construction is lacking.
In this study, we conducted CT tests with some structural glued-laminated timber.
The wood species are Scots Pine, Japanese Larch and Japanese cedar, they
frequently are processed into structural glued-laminated timber (hereinafter
referred to as “glulam”).
We used initial crack-lengths and thickness as parameters. The ratios, a0/W, are
0.26, 0.41, 0.50, 0.6, these values were referred to JSME. Thicknesses are 47mm,
94mm and 150mm.
As the results, in the case its thickness is under 94mm and the a0/W is over 0.50,
we can see ductile fracture of wood in stable, we can obtain stable value of Jintegral
for crack initiation.