Research of Form Causation of Knot Types of Chinese Fir Structural Lumbers
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is one of main timber species used commercially in China which has many desirable characteristics, and the plantation area is quite widely. For the different knot size affects the appearance quality and degrades the mechanical properties greatly, therefore, it is necessary to do some research on knot of dimension lumber. Knot was one of most important characteristics which not only damaged the consistency of wood exterior quality, but also had great bad effect on mechanical properties. In theory, the texture deflection of the surrounding wood of knot was the main reason for degrading wood mechanical properties. As the dependent branch, growth status was the key factor to knot distribution and size in branch. For the knot wood was harder than others wood, so the fibber twist surrounding the knot, not the knot itself, was the reason for the strength decreasing. In ! 998, Zhang did some research on the relation of site density and branch, knots for balsam fir, and also explored the effects of site density on lumber strength and rigidity. But at present, few national forest owners took measures on pruning for Chinese fir, and few research and reports was about pruning on Chinese fir in China.
REN Hai-qing GUO Wei FEI Ben-hua LUO Xiu-qin LI Xia-zhen
Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China Beijing Forestry Machinery Research Institute, State Forestry Administration, Beijing 100029, China
国际会议
International Symposium on Wood Science and Technology(IAWPS 2008)(国际木材产品学会联合会2008学术研讨会)
哈尔滨
英文
223-224
2008-09-27（万方平台首次上网日期，不代表论文的发表时间）