基于硬头黄竹材质变异分析的伐竹年龄判定  

Logging age for the Bambusa rigida culm based on physical-mechanical properties

作　　者：李凤[1] 齐锦秋[1] 肖辉[1] 陈玉竹[1] 谢九龙[1] 黄兴彦[1] 

机构地区：[1]四川农业大学林学院,四川成都611130

出　　处：《浙江农林大学学报》2017年第5期849-855,共7页Journal of Zhejiang A&F University

基　　金：四川省教育厅高校木材工业与家具工程重点实验室资助项目

摘　　要：以四川产硬头黄竹Bambusa rigida为研究对象,参考国家标准GB/T 15780-1995《竹材物理力学性质试验方法》与竹材径向加压抗弯性质测定方法,并结合单因素方差分析方法(ANOVA),对竹龄为0.5~4.5 a的竹材物理力学性质进行研究,为硬头黄竹择龄伐竹提供参考。结果表明:(1)竹龄在0.5~4.5 a间,竹材生材含水率、干缩率逐渐减小,基本密度逐渐增大;(2)竹龄为3.5 a时,竹材顺纹抗压强度、抗弯强度和抗弯弹性模量达到最大,顺纹抗剪强度达到稳定;(3)由竹秆基部至梢部,竹材生材含水率、干缩率呈下降趋势,基本密度、顺纹抗压强度、顺纹抗剪强度、抗弯强度与抗弯弹性模量呈增大趋势,而顺纹抗剪强度、抗弯强度与抗弯弹性模量在竹龄为4.5 a的竹秆梢部出现下降;(4)竹龄为3.5 a的竹材材性基本达到稳定,生材含水率、基本密度、干缩率、顺纹抗压强度、顺纹抗剪强度、抗弯强度、抗弯弹性模量分别为60.67%,0.72 g·cm^(-3),12.54%,82.41 MPa,11.99 MPa,237.13 MPa和8.32 GPa。推荐材质成熟的硬头黄竹伐竹年龄为3.5 a。To optimize the logging age of the Bambusa rigida culm,physical-mechanical properties of bamboo culms aged from 0.5 to 4.5 years were sampled by age with sample size of 10 for each age bamboo culm and evaluated according to national standards from Testing Methods for Physical and Mechanical Properties of Bamboos（GB/T 15780-1995） and the radial bending test method.Data from different bamboo ages were statistically analyzed with ANOVA.Results showed that（1） the moisture content of green bamboo and volumetric shrinkage decreased with an increase in bamboo age from 0.5 to 4.5 years;whereas,the basic density increased overall.Also,（2） compression strength parallel to the grain,modulus of rupture（MOR）,and modulus of elasticity（MOE） reached a maximum at 3.5 years of age,and shear strength parallel to the grain had already leveled off at this age.（3） From the base to the top portion of the bamboo culm,moisture content of the green bamboo and volumetric shrinkage decreased;whereas,the basic density,compression strength parallel to the grain,shear strength parallel to the grain,MOR,and MOE all increased.Noteworthy was that shear strength,MOR,and MOE decreased at the top portion of the bamboo at age 4.5,which reflected the aging phenomenon of bamboo culms.（4） The 3.5-year-old bamboo culms had a moisture content of green bamboo,60.67%;basic density,0.72 g·cm^-3;volume shrinkage,12.54%;compression strength parallel to the grain,82.41 MPa;shear strength parallel to the grain,11.99 MPa;MOR,237.13 MPa;and MOE,18.32 GPa.Comprehensively,a matured 3.5-year-old Bambusa rigida culm was recommended as the optimal logging age.

关 键 词：木材科学与技术 硬头黄竹 物理性质 力学性质 伐竹年龄 

分 类 号：S781.9[农业科学—木材科学与技术]