On the Influence of Varying Aperture on Flow Mechanisms in an Initially Dry Vertical Smooth Parallel Fracture Under Free-Draining Conditions

K. P. Segole and J.L. Van Rooy. September 2017.

Proceedings of the 9th YGE Conference, Durban.

It is essential to understand the properties and behaviour of rock mass, mainly in a hydrogeological context as well as various geotechnical applications. However, most of these processes occur as bulk fluid flow in the unsaturated zone and single fracture flow becomes imperative in understanding these processes, including, the identification of fluid flow mechanisms. The research presented in this paper investigates the influence of aperture, in a single smooth parallel plate model, on flow mechanisms under conditions of variable saturation. Visual experiments illustrate that liquid migration and to a lesser extent flow structures, are affected by varying the fracture aperture.







Varying Aperture on Flow Mechanisms

Improved understanding of variably saturated fracture flow in unsaturated rock masses has numerous implications, especially when considering the complexity, heterogeneity and anisotropy of the fractured vadose zone.  Specifically, better quantification of groundwater flow has application in; permeability assessments for dam foundation rock masses, water inflow into deep mines, subsurface tunnels, and large rock caverns

Key Words: 

Fracture aperture, variable saturation, smooth parallel plate model.