选用四种不同土质试样设计相关试验,利用直接法和间接法结合不同扫描条件下的CT数变化曲线,研究扫描电压、对准模式、滤波函数、试样尺寸等CT扫描参数对岩土试样CT图像的具体影响,研究结果表明:扫描电压和滤波函数对岩土CT图像和CT数影响较大;对准模式和重建矩阵对试验结果影响非常小;滤波函数对岩土CT图像的增强或抑制作用取决于所选择的滤波函数的属性,而与试样的土质无关;最后给出了CT扫描参数选择的原则,借助于合理的CT扫描参数,从而提高CT岩土图像的质量,获得相对准确的岩土CT值。
This paper designs a set of experiments to choose four different soil samples and studies the specific CT scanning parameters, which impact on the quality of rock and soil samples tomograms by use of direct method and indirect method and combining with the CT number changes. The parameters include the scanning voltage, the collimation mode, the filtering function, the samples size et al. The results showed that the scanning voltage and the filtering function have a great impact on rock and soil samples tomograms and CT numbers; the collimation mode and reconstruction matrix has little effect on the experiment results; The tomograms enhancement or inhibition depend on the chosen filter function properties, and have nothing to do with the soil. The following work provides the optimal principle of CT scanning parameters to improve the quality of rock and soil tomograms and obtain a relatively optimal CT numbers of rock and soil by means of the reasonable scanning parameters.