Journal of the South African Institution of Civil Engineering
On-line version ISSN 2309-8775
KIRSTEN, H A D; HEATH, G J; VENTER, I S and OOSTHUIZEN, A C. The issue of personal safety on dolomite: Update of a probability-based evaluation with respect to single-storey residential houses. J. S. Afr. Inst. Civ. Eng. [online]. 2014, vol.56, n.2, pp. 78-85. ISSN 2309-8775.
ABSTRACT Sinkholes may be treated as a chance phenomenon of which the likelihood of occurrence is a key parameter in determining their effect on public safety in the development of dolomite land. However, determining the likelihood of the occurrence of sinkholes remains a complex if not evasive problem in view of the sparsely populated datasets available at present. Three approaches to determining the likelihood of sinkhole occurrence that were developed over a period of time are reviewed and comparatively evaluated. The geological time-based return periods postulated for a residential infiltration regime in the third approach is applied to determine the maximum allowable population densities for a single-storey residential house development as an update of a previous paper on the problem. The maximum population densities based on this updated approach were found to be one and a half to three times larger than those previously considered to be allowable for Inherent Hazard Classes 1, 2 and 3. This relaxation on the historically established empirical rules on population density is considered by the authors to better represent observations in recent years.
Keywords : dolomite; sinkhole; risk; hazard; coincidence; probability; single houses.