Fit-for-purpose certification of bituminous road construction products in South Africa

The technological trajectory of scale intensive sectors, such as the civil engineering sector, is characterised by slow and incremental technological innovation. In road construction, uncertainty on product performance leads to conservative design approaches. There is considerable reluctance to experiment with new technologies, especially when products fall outside the scope of existing standards and specifications. In order to reduce the uncertainty on the use of non-standard products and to promote innovation, various countries, including South Africa, have set up technical assessment organisations. The objective of this paper is to discuss the process followed in developing guidelines for the technical assessment of ultra-thin friction courses (UTFC) and cold mix material for patching and pothole repair, as well as present some of the experience gained in the assessment of these products. The selection of performance specifications for these product types is discussed, as are the typical modes of failure observed in the field. The technical assessments have shown for which applications products are suitable and this reduces uncertainty around product performance. The number of product assessments is expected to increase as more road authorities start specifying the use of certified products.