Abstract:
The collapse of residual Archaen granitic soils in South Africa is a geotechnical hazard that was
identified in the 1950’s. Collapse has led to hazardous building conditions in the rapidly
expanding northern parts of Johannesburg, and in areas stretching across the eastern parts of
South Africa, encompassing KwaZulu Natal, Mpumalanga and Limpopo Provinces. Since the
development of the oedometer test in the 1960’s and the research of Jennings and Knight in the
1970’s very little further research has been done on the topic of collapse, despite the
development of a number of new testing procedures that can give insight into the properties of
these soils. Due to the large surface area of South Africa prone to collapse, and the lack of
knowledge and testing methods to identify and quantify this hazard the author felt, that further
insight into the collapse of residual Archaen granitic soils was required.
This research serves to evaluate the properties of Archaen residual granitic soils that may be
indicative of collapsible soils. The research also compares various test methods and apparatus
used to identify and quantify collapse potential, namely the oedometer collapse potential test
and the triaxial collapse potential test, and evaluates the effect of soil properties on these
methods.