含水率对意杨PF-LVL弹性模量的影响  

Effect of Moisture Content on the MOE of the PF-bonded Poplar LVL

作　　者：孙伟[1] 董春雷[1] 张宏健[1] 

机构地区：[1]西南林业大学材料工程学院

出　　处：《林产工业》2013年第3期14-18,共5页China Forest Products Industry

基　　金：国家自然科学基金31170534资助

摘　　要：对从10.9%吸湿到25%再吸水到33%,接着蒸发回到25%再解吸回到10.9%的一个循环内多点含水率(MC)下的意杨酚醛树脂单板层积材(P-PF-LVL)静曲弹性模量(MOE)的测试分析结果表明:仅一个周期(MC 10.9%～33%～10.9%)的增水和失水,就导致P-PF-LVL产生了31.36%初始MOE的永久性损失,其中,源自于热压压缩永久性厚度回复的有4.61%;初始MOE最大可下降56.66%,初始厚度最大可增加4.84%,其中,热压压缩的永久性厚度回复有2.76%。P-PF-LVL的纤维饱和点为25%左右,其特征与一般实木有所不同。研究结果有助于结构用LVL的设计、制造和性能控制。Results from the test and analysis of the bending modulus of elasticity （MOE） at several levels of moisture content （MC） of the PF-bonded laminated poplar veneer lumber （P-PF-LVL） show that after only one cycle of increasing and decreasing of MC （10.9%-33%-10.9%）, 31.36% of the initial MOE of the PF-bonded poplar laminated veneer lumber （P-PF-LVL） loses permanently, in which 4.61% is from the permanent thick- ness recovery of the compression caused by hot pressing. The maximum loss of MOE can be 56.66% of the initial one. The maximum thickness swelling can be 4.84% of the initial thickness, in which 2.76% is from the perma- nent recovery of the compressed thickness. It is also found that the fiber saturation point of the P-PF-LVL is about 25% and its characteristics are quite different from those of common solid wood. All these achievements may be valuable for design, manufactory and quality control of the structural LVL.

关 键 词：意杨PF—LVL 静曲弹性模量 含水率 湿胀干缩 压缩回复 

分 类 号：TS653[轻工技术与工程]