中国工程科学
中國工程科學
중국공정과학
ENGINEERING SCIENCE
2014年
4期
25-29
,共5页
图像解析法%树盘%干缩异向性%干燥应力%弦向应变
圖像解析法%樹盤%榦縮異嚮性%榦燥應力%絃嚮應變
도상해석법%수반%간축이향성%간조응력%현향응변
image analytical method%wood disks%shrinkage anisotropy%drying stress%tan-gential strain
研究探讨了干燥过程中树盘受抑制干缩应变、自由干缩应变、弹性应变、黏弹性蠕变应变以及机械吸附蠕变的图像解析测算法；运用该方法测算了白桦树盘常规缓慢干燥（含水率分布均匀）过程中干缩异向性引起的弦向各应变，分析了干燥过程中不同含水率阶段的应力状态及应力与各应变的关系。结果表明：应变的图像解析测算法可满足精度要求；树盘干燥至fiber saturation point( FSP)以下，弦向首先受拉伸应力作用，随着干燥的进行，拉伸应力转变为压缩应力；应力方向与各应变对应关系不同，与黏弹性蠕变应变无明显对应关系，与机械吸附蠕变基本对应。
研究探討瞭榦燥過程中樹盤受抑製榦縮應變、自由榦縮應變、彈性應變、黏彈性蠕變應變以及機械吸附蠕變的圖像解析測算法；運用該方法測算瞭白樺樹盤常規緩慢榦燥（含水率分佈均勻）過程中榦縮異嚮性引起的絃嚮各應變，分析瞭榦燥過程中不同含水率階段的應力狀態及應力與各應變的關繫。結果錶明：應變的圖像解析測算法可滿足精度要求；樹盤榦燥至fiber saturation point( FSP)以下，絃嚮首先受拉伸應力作用，隨著榦燥的進行，拉伸應力轉變為壓縮應力；應力方嚮與各應變對應關繫不同，與黏彈性蠕變應變無明顯對應關繫，與機械吸附蠕變基本對應。
연구탐토료간조과정중수반수억제간축응변、자유간축응변、탄성응변、점탄성연변응변이급궤계흡부연변적도상해석측산법；운용해방법측산료백화수반상규완만간조（함수솔분포균균）과정중간축이향성인기적현향각응변，분석료간조과정중불동함수솔계단적응력상태급응력여각응변적관계。결과표명：응변적도상해석측산법가만족정도요구；수반간조지fiber saturation point( FSP)이하，현향수선수랍신응력작용，수착간조적진행，랍신응력전변위압축응력；응력방향여각응변대응관계불동，여점탄성연변응변무명현대응관계，여궤계흡부연변기본대응。
This study investigated the image analytical method which was used to measure the tangential strains, including practical shrinkage strain, free shrinkage strain, elastic strain, viscoelastic creep strain, and mechano-sorptive (MS) creep, which caused by shrinkage anisotro-py during slow conventional drying of wood disks. Also we analyzed the stress in different moisture content (MC) and the relations between stress and strain. The results showed that the image analytical method could meet the requirements in accurate level;below the fiber satura-tion point (FSP), the wood disks were initially subject to tangential tensile stress;with the de-creasing MC, the tensile stress turned into compressive stress. The relations between stress and strain were complex. It had no obviously corresponding connections with the viscoelastic creep strain, and it was almost corresponding with the MS creep.
