﻿ 木材断口分形的初步研究
 林业科学  2006, Vol. 42 Issue (3): 104-107 PDF
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#### 文章信息

Fei Benhua, Qin Daochun, Yang Zhong.

An Approach to Study the Fractal Character of Wood?

Scientia Silvae Sinicae, 2006, 42(3): 104-107.

### 作者相关文章

An Approach to Study the Fractal Character of Wood?
Fei Benhua, Qin Daochun, Yang Zhong
Research Institute of Wood Industry, CAF  Beijing 100091
Abstract: It is very difficult to characterize the fracture surface of wood with traditional way because of its irregularity and complexity. This paper, inspired from slit island method (SIM) and mass fractal method, proposes a new method, by which the change of sectional area with spatial location in wood fractures can be determined, to quantify the character of fracture surfaces. The experiment is done by continuously microtoming a fractured sample embedded with paraffin at intervals of hundreds micron along the longitudinal axis from tip to end of fracture. The results indicate there exists a linear correlation between the area and the corresponding location in a double logarithm coordinate. The slope, here termed as section variation dimension (DL), is located between 2.23 to 2.75 with the DL of pressed zone being smaller than that of tensile zone for a wood fractured by static bending, and DL can be used to describe quantitatively the complexity of fracture surface of wood.
Key words: wood    fracture    fractal    section variation dimension

1 材料与方法 1.1 材料

1.2 取样方法

 图 1 木材断口切片的取样位置 Fig. 1 Sampling location of wood fracture for slicing
1.3 面积测量

1.4 维数计算

2 结果与讨论

 图 2 木材断口横切面的轴向变化(试样D的受压部分) Fig. 2 Axial variety of cross section of wood fracture(pressed zone of sample D)

 图 3 杨树静曲破坏试样断口的位置-面积间的关系 Fig. 3 Location-area relationship for fractures in poplar samples fractured by static bending

3 结论与建议

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