密度和含水率对重组竹顺纹抗拉强度的影响  

Effects of Density and Moisture Content on the Tensile Strength Parallel to Grain of Bamboo Scrimber

作　　者：盛叶 黄庚浪 叶小凡 廖飞宇 杨文斌[2] Sheng Ye;Huang Genglang;Ye Xiaofan;Liao Feiyu;Yang Wenbin(College of Transportation and Civil Engineering,Fujian Agriculture and Forestry University, Fuzhou 350002;College of Material Engineering,Fujian Agriculture and Forestry University, Fuzhou 350002)

机构地区：[1]福建农林大学交通与土木工程学院,福州350002 [2]福建农林大学材料工程学院,福州350002

出　　处：《林业科学》2024年第10期116-121,共6页Scientia Silvae Sinicae

基　　金：国家科技项目备案类(2023L3046);福建省科技计划项目(星火项目)(2022S0029);中建股份科技研发项目(CSCEC-2022-Z-58)。

摘　　要：【目的】探究不同密度和含水率下重组竹顺纹抗拉强度的变化规律,提出重组竹顺纹抗拉强度与密度、含水率的相关模型,为推进重组竹在工程中的应用提供依据。【方法】参考ASTM D143—14《木材无疵小试样的标准试验方法》,选取不同密度(1.1、1.2、1.3 g·cm^(-3))和含水率(4%、8%、12%、16%、20%)的重组竹试件进行正交抗拉试验,分析重组竹顺纹抗拉的主要破坏形态;采用线性模型和抛物线模型拟合重组竹顺纹抗拉强度随密度的变化规律,采用线性模型和ASTM模型拟合重组竹顺纹抗拉强度随含水率的变化规律,提出重组竹顺纹抗拉强度在密度和含水率双因素影响下的耦合模型。【结果】重组竹顺纹抗拉的主要破坏形态为平口破坏和斜口破坏,重组竹密度越大,平口破坏概率越大;重组竹含水率越大,斜口破坏概率越大。基于试验研究和数据拟合提出重组竹顺纹抗拉强度的单因素影响模型和双因素耦合模型,理论结果与试验结果吻合良好。【结论】在本研究密度范围内,重组竹顺纹抗拉强度随密度增加而增大、随含水率升高而减小。线性组合模型和ASTM组合模型均能较好预测重组竹顺纹抗拉强度在密度和含水率双因素影响下的理论值,线性组合模型计算更为简便,在实际预测中建议直接使用线性组合模型。【Objective】This study intends to provide a basis for promoting the application of bamboo scrimber in engineering by studying the variation of tensile strength of bamboo scrimber along the grain under different densities and moisture contents.【Method】By referring to《Standard Test Methods for Small Clear Specimens of Timber》(ASTM D143—14),bamboo scrimber specimens with different densities(1.1,1.2,1.3 g·cm^(-3))and moisture contents(4%,8%,12%,16%,20%)were selected for orthogonal tensile test,analyzed the tensile failure modes of bamboo scrimber parallel to grain under different density and moisture content,the linear model and parabolic model were used to fit the variation tensile strength of bamboo scrimber parallel to grain with density,and the linear model and ASTM model were used to fit the variation of tensile strength of bamboo scrimber parallel to grain with moisture content.Finality,the coupling model of tensile strength of bamboo scrimber parallel to grain with the influenced of density and moisture content was proposed.【Result】The main failure forms of bamboo scrimber parallel to grain under tension were flat failure and oblique failure.The flat failure was more prone to happen with the increasing density of scrimber bamboo.and the oblique failure was more prone to happen with the increasing moisture content of bamboo scrimber.Through experimental research and data fitting,the single parameter model and the two parameter coupling model of the tensile strength of bamboo scrimber parallel to grain were proposed respectively.The theoretical results were in good agreement with the experimental results.【Conclusion】Within the density range of this study,the tensile strength of bamboo scrimber parallel to grain increased with the increase of density.The tensile strength of bamboo scrimber parallel to grain decreased with the increase of moisture content.The linear combination model and the ASTM combination model can predict the theoretical value of the tensile strength of bamboo scrimber pa

关 键 词：重组竹 顺纹 抗拉强度 密度 含水率 

分 类 号：S781.9[农业科学—木材科学与技术]