Size effect of length on tensile strength of visually-graded Chinese fir dimension lumber

被引：0

作者：

Zhou H.-B. ^{[1
]}

Ren H.-Q. ^{[1
]}

Lü J.-X. ^{[1
]}

Jiang J.-H. ^{[1
]}

Wang X.-S. ^{[2
]}

机构：

[1] Research Institute of Wood Industry, Chinese Academy of Forestry

[2] College of Sciences, Beijing Forestry University

来源：

Jianzhu Cailiao Xuebao/Journal of Building Materials | 2010年 / 13卷 / 05期

关键词：

Dimension lumber; Size effect; Tensile strength; Timber constructions; Visual grades;

D O I：

10.3969/j.issn.1007-9629.2010.05.016

中图分类号：

学科分类号：

摘要：

Length size effect is one of important factors to adjust tensile strength of dimension lumber to an allowable property. The relationship between the tensile strength and the length of Chinese fir visually-graded dimension lumber was investigated. 412 dimension lumbers were divided into two groups: high visual grades(H) and low visual grades(L), and then sorted into three matched test sub-groups for each visually-graded group by dynamical modulus of elasticity. Three test spans (150 cm, 200 cm and 250 cm) were selected and the tensile strength property was tested. The length size effects of 5th and 50th percentiles of tensile strength were estimated by the slope method and the parametric method. Using nonparametric estimates, the estimated length effect parameters of H and L are 0.12 and 0.25 for the 5th percentile and 0.17 and 0.29 for the 50th percentile, respectively. The parameters of L are larger than those of H. The length size effect could be used when using the dimension lumber for practical purposes. When two-parameter Weibull distribution functions are fitted to the strength data, the estimated shape parameters of the Weibull distribution by the parametric method are almost identical to the inverse of nonparametric parameters except for the 5th percentiles for H.

引用

页码：646 / 649

页数：3

共 9 条

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