摘要
为了预测重组竹制品在实际使用中的寿命,基于X射线计算机断层扫描技术(X-ray computed tomography technology,X-CT),采用标准BS EN 1087-1:1995作为重组竹湿热耦合老化条件,以其CT值和老化分析指标的数学模型评估重组竹湿热耦合老化后结构强度的损失。结果表明:重组竹老化后密度、内胶合强度和CT值均小于老化前,且老化前后差异显著。随老化时间增加,其密度、内胶合强度和CT值的损失均增加,且变化趋势基本一致,在1~2h阶段变化较大,在2.5~4.5h阶段变化较平缓,在老化4.5h时达到峰值;将CT值差值与密度差值拟合为线性模型,模型相关系数R^2=0.9270,验证模型R^2=0.9438。CT值差值与内胶合强度差值拟合为Allometric模型,模型相关系数R^2=0.9488,验证模型R^2=0.9439;竹材自身的植物学特征及重组竹压制工艺造成了试验数据离散及老化前后离散程度发生改变。可通过改善重组竹制备工艺提高其内部均匀性及降低老化前后离散程度变化,以提高模型预测精度。
To predict their lifespan of reconstituted bamboo products in practical use,X-ray computed tomography technology（X-CT） was employed and the standard of BS EN 1087-1：1995 was used as the hydrothermal aging condition of recombinant bamboo.The loss of structural strength was evaluated by the mathematical model of the CT value and the aging analysis indicators after hydrothermal aging of reconstituted bamboo.The results show that：the density,the internal bond strength and the CT value of recombinant bamboo are decreased after aging than before aging,and the differences are significant before and after aging.With the increasing of the aging time,the losses of the density,the internal bond strength and the CT value are increased and their changing trends are basically the same,which rapidly change in 1-2 hand gently change in 2.5-4.5 hand reach the peak at 4.5 h;the CT value difference and the density difference are fitted into linear model whose model correlation coefficient R^2 and validation model R^2 are 0.9270 and 0.9438,respectively,and the CT value difference and the internal bond strength difference are fitted into Allometric model whose model correlation coefficient R^2 and validation model R^2 are 0.9488 and 0.9439,respectively;the botanical characteristics of bamboo and the press technology of reconstituted bamboo cause the discretizing of the experimental data and the change of the discretizing before and after aging.The internal uniformity of reconstituted bamboo can be improved and the change of the discretizing before and after aging can be reduced by improving the press technology to enhance the prediction accuracy of the models.
作者
王卿平
费本华
蒋明亮
刘杏娥
杨淑敏
WANG Qingping;FEI Benhua;JIANG Mingliang;LIU Xing＇e;YANG Shumin(Bamboo and Rattan Science and Technology Laboratory, International Center for Bamboo and Rattan, Beijing 100102, China;Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China;College of Materials Science and Technology, Beijing Forestry University, Beijing 100083, China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2018年第4期989-998,共10页
Acta Materiae Compositae Sinica
基金
国家重点研发计划(2016YFD0600904)
林业公益性科研专项(201304513)
国家自然科学基金(31670565)
关键词
X-CT技术
重组竹
湿热耦合老化
密度
内胶合强度
X-CT technology
recombinant bamboo
hydrothermal aging
density
internal bond strength
