Black spot analysis : infrastructure impacts on black spots in the Western Cape N1

This thesis discusses the infrastructural, vehicular and environmental factors that contribute towards road accidents. The role of infrastructure in improving road safety is the primary focus of the research, as infrastructure influences the driving experience. Road design and geometry are important for the consistency of highway performance. Road curvature, paved shoulders and the presence of an at grade intersection influence the drivers’ perception of the highway. The Laingsburg Beaufort West N1 highway has a high incidence of accidents, namely single vehicle accidents. For this reason, the road section has been classified as a hazardous location. These fatal accidents may be influenced by the infrastructural and geometrical factors of the highway. Western Cape geographical data was analysed for the period 2000 to 2007, to investigate the infrastructural and geometrical factors that influence the high accident rate. This was done through an ArcGis analysis, which gave insight into the properties of each of the fatal accidents. In order to get a level of confidence from the findings of the ArcGis analysis, a road safety audit was conducted. This was done through a general inspection of the N1 highway between Laingsburg and Beaufort West, which included driving through the road section at a constant speed, and completing a checklist of the operating elements of the highway. The road safety audit revealed that infrastructural problems (lack of guardrails, sign posts located close to highway) and geometrical factors (average paved shoulder width, single carriageway roads, and dangerous intersections) were present on the road. The Laingsburg Beaufort West analysis was the primary focus of the research. Data for the years 2010 to 2013, which was updated, was obtained from SANRAL and investigated for accident types and potential hotspots. An ArcGis analysis was also performed on the data. Fatal accidents were analysed, to determine whether the Provincial Government of the Western Cape would meet their accident reduction goals of reducing accidents by 50% between the years 2009 and 2014. A high incidence of fatal pedestrian accidents was observed in the Khayelitsha area. Recommendations include the relocation of poles and signs, increasing the paved shoulder width, installation of guardrails along the entire highway, as well as provision of pedestrian bridges and walkways in the Khayelitsha area.

Grantor dc:publisher.institution

Department of Civil Engineering

Year dc:date.issued

2014

Author dc:creator

• Dinga, Nasiphi

Advisor dc:contributor.advisor

• Vanderschuren, Marianne

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/13199

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/13199