岩石断面的分形测量及其分维的计算

在实验室内使岩石单轴压缩直至破裂,用位移传感器测量其断面高度,用显微镜观测断面切片的剖线,所得数据用尺度法计算其分维,各种岩石的不同曲线的分维在1.002-1.028之间,与野外断层主迹线分维值相同.用切岛法计算整个断面的分维约为2.05左右.有关分析和计算认为,分维的大小与岩石破裂时所受力的方向有关,与采样步长有关,而与岩石样品的大小无关.

THE FRACTAL DIMENSION OF THE FRACTURED SURFACE OF ROCKS

The rock samples are compressed uniaxially to fracture in the laboratory, then the heigtlis of fractured surfaces are digitized with 1×1 mm steps by using a displacement transducer, the profiles of rock slices are enlarged and sampled by a microscope and its attached equipment. The data of profiles are calculated by using the ruler method. The fractal dimensions of different profiles of various rocks are about 1.002-1.028, which is consistent with that of the main trace of faults in fields. By means of the slit island method, the fractal dimension of the whole fractured surfaces are calculated, which is about 2.05. The further analysis and calculation suggest that the fractal dimension of profiles may be related to the direction of acting force, and to the different sampling steps, but not to the size of rock samples.