基于离散标准节理粗糙度系数曲线的粗糙单裂隙等效水力隙宽的确定

Determination on Hydraulic Aperture of Single Rough Fractures Based on Standard Curves of Discrete Joint Roughness Coefficient

鉴于节理粗糙度、力学隙宽及迹线是影响确定粗糙单裂隙等效水力隙宽的三个关键因素,在既有研究的基础上,将光滑平行板和Barton提出的10条标准节理粗糙度系数曲线数字化,应用Fluent软件对不同节理粗糙度系数和不同力学隙宽模型进行数值模拟,探讨了节理粗糙度系数、力学隙宽、迹线与等效水力隙宽之间的关系。并与立方定理修正公式进行对比,结果表明等效水力隙宽随力学隙宽增大而线性增大,随节理粗糙度系数的增大而减小,并且考虑实际迹线情况的等效水力隙宽较不考虑的大。因此,在实际工程中,可采用所提出的拟合公式判断自然粗糙裂隙的渗透能力。

Since the joint roughness, mechanical aperture and seepage path are the three key factors that influence the hydraulic aperture of single rough fractures, based on previous studies, the smooth parallel plates and 10 joint roughness coefficient （JRC） standard curves introduced by Barton are digitized. Numerical simulations by Fluent are performed with different JRC and different mechanical apertures to discuss the relationship between hydraulic aperture and mechanical aperture, JRC and seepage path. Finally, the relationships are compared with the previous modified cubic law. The results indicate that the equivalent hydraulic aperture increases linearly with increasing mechanical aperture and decreases with increasing JRC. The hydraulic aperture in the situation of considering seepage path is larger. In practical engineering, the fitting formula introduced in this study is suggested to apply to judge the infiltrability of natural rough fractures.