论文部分内容阅读
粗糙表面对节理渗流影响显著,但难以定量描述,几何分形作为描述岩石节理表面形貌特征的一种方法,近年来得到了广泛应用。为了准确表述节理表面粗糙形态对节理渗流的影响,基于节理接触面积和开度,结合节理面分形特征影响,建立节理面水力开度计算分形修正公式。以自然节理试件为原型预制类岩石材料节理试件,通过激光测试获取节理表面三维形貌数据,应用立方体覆盖法计算节理试件的分形维数,并进行剪切–渗流耦合试验,计算剪切试验过程中水力开度变化规律。同时计算节理试件平均开度以及接触面积比在剪切过程中的变化规律,并应用Zimmerman计算公式、Yeo修正计算公式和分形修正公式分别计算节理面的水力开度,将计算结果与实测值进行比较。分析表明:分形修正公式与试验测试值吻合较好,实现了节理面接触面积、节理开度和节理面分形维数的良好耦合,能更为全面地描述节理面的渗流特性,具有较好的适用性。
Rough surface has a significant influence on the seepage of joints, but it is difficult to describe quantitatively. Geometric fractal, as a method to describe the surface topography of rock joints, has been widely used in recent years. In order to accurately describe the effect of joint roughness on joint seepage flow, a fractal correction formula for hydraulic opening calculation of joint surface is established based on the joint contact area and opening degree, combined with the fractal characteristics of joint surface. The natural joint specimens were taken as the prototype prefabricated rock material joint specimens. The three-dimensional topography data of the joint surfaces were obtained by laser test. The fractal dimension of the joint specimens was calculated by the cube covering method, and the shear-seepage coupling test was carried out. Cut the hydraulic opening during the test changes. At the same time, the average opening of the joint and the change rule of the contact area ratio during the shearing process were calculated. The hydraulic opening of the joint was calculated by Zimmerman calculation formula, Yeo correction formula and fractal correction formula respectively. The calculated results were compared with the measured values Compare. The analysis shows that the fractal correction formula is in good agreement with the experimental test value, and the good coupling of the contact area, the joint opening degree and the fractal dimension of the joint surface can be achieved, and the seepage characteristics of the joint surface can be described more fully applicability.