学术
摘 要:
采用水热处理对杨木进行压缩前预处理，比较不同水热处理条件与冷却时间对试件顺纹压缩性质的影响。结果表明：水温对木材抗压强度有较大影响，随着水温的升高，木材的顺纹抗压强度与屈服应力均呈下降趋势，而屈服应变变化很小，最大载荷下的应变和载荷陡降时的应变均增加，残余变形增加。保温时间对木材的顺纹抗压强度影响不显著，随着保温时间的延长，最大载荷下应变与应变差先增加，在保温1h时应变达到最大值，而后减小直至趋于平缓。杨木在水温为100℃保温时间为1h水热处理后，最易被压缩，试件的强度均最低，应变最大。随着冷却时间的延长，抗压强度与屈服应力呈小幅度的增加，当冷却到一定时间，其值不再增加。[著者文摘]
文章出处:
《南京林业大学学报：自然科学版》-2008年32卷1期 -61-64页
栏目信息:
分 类 号:
文献标识码:
A
文章编号:
1000-2006（2008）01-0061-04
Effect of hydrothermal treatment on longitudinal compression properties of poplar
ZHOU Li, LU Xiao-ning, DING Hui （College of Wood Science and Technology Nanjing Forestry University, Nanjing 210037 ,China）
Abstract:
The study dealt with the pretreatment of poplar （Populus deltoides Bartr. ＂Lux＂） by using hydrothermal treatment before it was compressed, which compared the influence of different treatment conditions and cooling time on the longitudinal compression properties. The results of experiment analysis showed that the effect of the water temperature on the compression strength is obvious. Along with the water temperature increasing, the compression strength and yield stress all present the descending trend. The change of the yield strain is very little. The strain at the maximum force and the strain at the largely decreased force all present increasing trend. The remained strain increases. The effect of heat preserving time on the longitudinal compression strength is not obvious. Along with the declay of the heat preserving time,the strain at maximum force and difference of strain increase first, when the heat preserving time reaches one hour,the strain is the largest,then the stain decrease until the value changes very little. The samples can be compressed easily, so the strengths are all the highest at the condition of heat preserving time one hour and water temperature 100℃. With the prolongation of cooling time, the compression strength and yield stress both increased slightly. When cooled for the special time, the compression strength and yield stress did not increased any longer. The results of experiment are the bases of the use and modification of the poplar.[著者文摘]
Key words:
Poplar ; Hydrothermal pretreatment ; Longitudinal compression
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