林业工程学报2017，Vol.2Issue(1)：41-45,5.DOI:10.13360/j.issn.2096-1359.2017.01.008
人工林杉木层板分级及性能研究
Study on the grading and property of plantation Chinese fir lamina
摘要
Abstract
According to the GB/T 50708-2012, visual grading and mechanical grading were used respectively to grade the plantation Chinese fir ( Cunninghamia lanceolata) . The applicability and scientific rationality of the two approaches were explored. By measuring and analyzing the annual ring width, absolute dry density, modulus of elasticity ( MOE) , and modulus of rupture ( MOR) of each lamina, the results showed that as for the visual graded lamina, the discreteness of MOE value was very high with no regularity, and its characteristic value ( at the average or 5% quantile) could not a⁃chieve the required standard value either;the discreteness of MOR was also very high and its eigenvalue increased with the development of the lamina�s grade level; the MOE and MOR of substandard lamina were higher than the original ones;there was no correlation between the density of lamina and MOR, while there was a little minus correlation be⁃tween annual rings width and MOR, and there was rather better positively correlation between MOE and MOR. By con⁃trast, under machanical grading, the eigenvalue of MOR increased proportionally with the development of lamina grade. The research results indicated that the way of visual grading has not been applicable to the grading of plantation Chinese fir by now since the MOR of visual graded lamina could not meet the processing requirement of glulam, while the ma⁃chanical grading could be applied to manufacture the glulam with reliable structural strength.关键词
杉木/层板/分级/年轮/弹性模量/静曲强度Key words
Chinese fir/lamina/grading/annual ring/modulus of elasticity ( MOE)/modulus of rupture ( MOR)分类
建筑与水利引用本文复制引用
乔鹭婷,谢力生,唐子燊,徐竹华..人工林杉木层板分级及性能研究[J].林业工程学报,2017,2(1):41-45,5.基金项目
湖南省高校创新平台开放基金项目（14K113）；国际科技合作专项（2014DFA53120）。 （）
