On Thursday, 04 February 2021 the University of Pretoria shared its latest doctoral research with GWD members:
The UP Department of Geology has for the past decade focused on how the soil and rock between land surface and the phreatic or saturated zone behave with respect to highly variable moisture contents.
They aim to contribute to knowledge on variably saturated flow through soil, rock defects, karst, and the interfaces between these media. This Talk on unsaturated hydraulics and the role of the vadose or unsaturated zone in engineering geology and hydrogeology was presented by past and current UP doctoral students:
The Session was facilitated by Prof Matthys A Dippenaar (Associate Professor: Engineering Geology and Hydrogeology) and Prof Louis J van Rooy (Associate Professor: Engineering Geology and Rock Mechanics) from UP Geology Department (www.up.ac.za/geology)
Please email all queries to: firstname.lastname@example.org
The following questions was raised and addressed during the session:
C Zermatten Q: Brandon- Is it correct to understand that your related experiments considered vertical flow from horizontal flow always to an open system (the cutting in the tunnel) and currently no information on vertical flow into a closed system?
C Zermatten Q: Mampho- Is it correct to understand that the lab tests used 1x shale sample and 1x quartzite sample (used repeatedly for wetting and rewetting etc)? (versus using multiple samples for comparison)
Did your work evaluate different types of shale (where mineralogical composition may be highly carbonaceous) and/or different extents of weathering of the shale (the photo you showed in the slides was quite pristine) – I would be interested to see your comparative results of weathered shale where the parting planes have opened to a greater extent.
C Zermatten Q: Duan- With regard to plant-soil interaction – have you been able to conceptualise the potential for site specific variability as a result of plant type (i.e. trees that are invasive, trees that are deciduous and trees
that are known to have an aggressive root system?
Frans van der Merwe Q : How effective is dam foundation grouting in an unsaturated rock mass? How do you ensure effectiveness?
A special thank you to the Water Research Commission for supporting research at the University of Pretoria.