基于“经典层板理论”,以早材和晚材作为基本单元,建立兴安落叶松成熟材单一年轮顺纹抗弯弹性模量以及顺纹抗拉强度的力学模型; 通过试验测得兴安落叶松成熟材早、晚材力学性能,并与理论模型值进行比较,探讨所建模型的准确性。结果表明:顺纹抗弯弹性模量模型的计算值与实测值相对误差集中分布在20%以内; 而顺纹抗拉强度模型的计算值与实测值相对误差均匀分布在60%以内。由此可得,以早、晚材为基本单元,建立兴安落叶松成熟材同一年轮的顺纹抗弯弹性模量力学模型方法可行。为提高单一年轮顺纹抗拉强度力学模型的求解准确性,需采用更精确的几何尺寸测量方法。
Abstract
To establish the mechanical modes of Larix gmelinii mature single annual ring(MSAR), including longitudinal modulus of elastic(MOE)and tensile failure load(LTF), classic Laminate theory was involved as the theoretical basic and MSAR was composition of earlywood(EW)and latewood(LW). Besides, in order to verify the both models, the mechanical properties of EW and LW were tested. The results showed that the relative errors of MOE model were concentrated fewer than 20%, while they were dispersed under 60% in LTF model. It concluded that it was possible to build Larix gmelinii MSAR mechanical models, of which base units were EW and LW. To improve the accuracy of LTF model, it was necessary to enhance test accuracy of specimen geometry. Moreover, to obtain more reliable mechanical properties of EW and LW mechanical parameters from MSAR, it requires further study on test methods for EW and LW.
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基金
收稿日期:2013-07-26 修回日期:2014-02-16
基金项目:国家林业公益行业科研专项项目(201104027)
第一作者:郭莹洁,博士。*通信作者:任海青,研究员。E-mail: Renhq@caf.ac.cn。
引文格式:郭莹洁,赵荣军,钟永,等. 兴安落叶松成熟材单一年轮顺纹力学模型[J]. 南京林业大学学报:自然科学版,2014,39(1):177-180.
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