Case Study: Mount Edgecombe Interchange –investigation, design and construction of a complex geotechnical project

Pequenino,F.P. Van der Merwe,F.H. Purchase,C. Warren-Codrington,C.J. 

October 2019. In Proceedings 17th African Regional Conference on Soil Mechanics
and Geotechnical Engineering

This paper discusses key observations and lessons learnt from the geotechnical investigation, design and construction for the four level Mt Edgecombe Interchange. The interchange is the largest and most complex yet to be constructed in South Africa and is situated on a weak succession of coastal sands and clays to depths of over 60m. A significant feature of the project was the geotechnical works. It is considered important to bring to the fore projects where the benefits of having adequate investigations, robust codes or client specifications, and meaningful roles for geotechnical engineers, contributed to its ultimate success.







A significant feature of the Mt Edgecombe Interchange project was the geotechnical works undertaken. A number of lessons were learnt over the decade long project; the authors regard the most significant being, the need for more comprehensive and prescriptive South African geotechnical design and investigation code(s), and greater attention paid to geotechnical aspects at the design stage. 


Geotechnical investigation, geotechnical design, geotechnical risk, geotechnical codes, geotechnical engineer,