两种国产藤材的抗弯性能及变异

Bending properties and the variation of two domestic commercial rattan cane

抗弯强度和抗弯弹性模量是藤材重要的力学性能指标,对藤材的合理利用及产品开发具有重要作用。本文对我国两种主要材用商品藤—单叶省藤(Calamus simplicifolius)和黄藤(Daemonorops margarita)藤材的抗弯弹性模量(MOE)、抗弯强度(MOR)及其变异进行研究,结果表明:1)两种藤材抗弯性能的株间差异不明显,但在株内生长高度方向上的差异极其显著;2)藤材抗弯性能与其生长年份密切相关,离基部越远,生长高度越大,即生长年份越小,藤材的MOE和MOR越小;藤材梢部的抗弯强度仅为基部的1/2;3)单叶省藤材的MOE和MOR与生长高度的多项式相关因子分别达到了0.96和0.98,黄藤材的MOE和MOR与生长高度的多项式相关因子分别达到了0.98和0.99;4)单叶省藤的破坏强度和破坏应变都比黄藤材大,其韧性系数高达黄藤材近4倍。单叶省藤材可作多种用途,而黄藤材则宜整藤利用。

The modulus of elasticity in bending and bending strength are important performance indicators of rattan cane, which play an important role in indicating cane reasonable utilization and cane product development. The Calamus simplicifolius and Daemonorops margarita are two most important domestic rattans providing commercial cane. The modulus of elasticity（MOE） in bending, bending strength（modulus of rapture, MOR） and their variation of two rattan canes were investigated. Results showed that：（1） the variations of cane bending properties were not notable between individual plants, but the differences were very significant along the growing height direction within plant;（2） the cane bending property was closely related to cane growth year; the longer from the cane base, i.e. the higher the growing height, indicating the younger the cane, the smaller the bending strength; the bending strength of cane tip was nearly half of that of cane base;（3） the cane bending properties and cane growing height had good polynomial relationship, the correlation coefficients between the MOE and MOR of Calamus simplicifolius cane and its growing height reached 0.96 and 0.98 respectively, and those for Daemonorops margarita cane reached up to 0.98 and 0.99 respectively;（4） the breaking strength and failure strain of Calamus simplicifolius cane were both bigger than those of Daemonorops margarita cane, and the bending toughness coefficient of the former was nearly three times bigger than that of the latter; thus the former cane could have various utilization forms, while the latter cane was advised to be used as a whole stem.