期刊论文

中文

林业工程学报

2096-1359

2017

2

1

41-45

10.13360/j.issn.2096-1359.2017.01.008

14K113:湖南省高等学校创新平台开放基金 2014DFA53120:国家国际科技合作专项基金

本校为第一机构

对人工林杉木层板按照GB/T 50708—2012进行目测分级和机械弹性模量分级,探讨两种分级方法的适用性和科学合理性。通过测定各层板的年轮宽度、绝干密度、弹性模量和静曲强度并进行处理与分析发现:对于目测分级,各等级层板的弹性模量值其离散度非常大且没有规律性,其特征值（平均值和5%分位值）也达不到标准规定的要求,静曲强度值的离散度也很大但其特征值随层板等级的提高而增大,等外层板的弹性模量和静曲强度值反而比等内层板的要大;层板密度与其静曲强度基本上没有相关性,而层板的年轮宽度与其静曲强度有一定的负相关性;层板的弹性模量与其静曲强度有较好的正相关性,采用机械弹性模量分级,静曲...

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 req...