排序方式: 共有2条查询结果,搜索用时 0 毫秒
1
1.
The main purpose of this study was to establish whether sugi lumber with an extremely low Young’s modulus, which is plentifully
produced in southern Japan, can be practically used as laminae for glued laminated timber (glulam) from the viewpoint of long-term
performance under loading. Bending creep tests were carried out on sugi (Cryptomeria japonica D. Don) glulam with extremely low Young’s modulus laminae (3–4 kN/mm2) for the inner layers, as were tests on hybrid glulam with Douglas-fir (Pseudotsuga menziesii Franco) laminae (14–15 kN/mm2) for the outermost layer and sugi laminae (including those with a Young’s modulus of 3–4 kN/mm2) for the inner layers. The specimens were eight glulam beams with different compositions that were 105 mm wide, 210 mm deep,
and 3980 mm long. The term of the creep test was 4 years. The results are summarized as follows. First, there were no significant
differences between the Young’s modulus or bending creep of glulam L30 (laminae with Young’s modulus of 3–4 kN/mm2) and that of glulam L50 (laminae with Young’s modulus of 5–6 kN/mm2) for the inner layers. Second, for asymmetric compositions, the behavior of increases and decreases of relative creep due
to atmospheric changes showed opposite behavior for glulam loaded from the side of lower Young’s modulus and from the side
of higher Young’s modulus. Third, the required experimental term for the creep test to estimate an accurate long-term curve
is 1 or 2 years (with data for the first 6 months excluded) when the power law is used for the estimation. Fourth, the values
of relative creep in 50 years obtained from the experimental term were much lower than 2, which is the standard value set
by Notification No. 1459 of the Ministry of Construction in Japan, and these values were not affected by the composition of
the laminae. 相似文献
2.
Satoe Aratake Agus Trianto Novriyandi Hanif Nicole J. de Voogd Junichi Tanaka 《Marine drugs》2009,7(4):523-527
A new polyunsaturated brominated fatty acid possessing acetylenic bonds 1 was isolated from the Indonesian sponge Haliclona sp. The structure of compound 1 was elucidated by analyzing its spectral data. It showed moderate cytotoxicity against cultured cells. 相似文献
1