The UK Department for International Development (DfID) and World Bank co-funded research into appropriate Low Volume Rural Road (LVRR) pavement and surfacing options is underway in Vietnam under the South East Asia Community Access Programme (SEACAP). Previously there has been a sector concentration on the provision of unsealed gravel roads, which, although relatively cheap to construct, are often unsustainable in the high rainfall; steep gradient or flood prone, environments prevalent in Vietnam.
The SEACAP 1 project involved the construction of LVRR trial roads in a representative selection of road environments in a number of provinces with diverse characteristics. A wide range of sub-base, base and surfacing options were trialled including bitumen emulsion, stone chip and sand seals. Standard local hot bitumen seals and unsealed options have been constructed as control sections. Construction was completed between June 2005 and July 2007 and representative lengths selected for long term condition monitoring. Initial performance information is now becoming available and this, together with the construction cost and construction quality assessment data, is allowing the development of practical Performance, Whole Life Cost and Technology Option Selection models.
This paper summarises the outcomes of SEACAP 1 to date with particular focus on the use of the bitumen emulsion seals in comparison with the local hot bitumen and unsealed options.