Low volume roads are an essential and integral component of the road system in all, particularly developing, countries where their importance extends to all aspects of the economic and social development of rural communities. Most of the current investment in new road projects involves upgrading these unsealed rural roads to a sealed standard. However, the design of this type of road is a challenging task in that: - Pavements may be constructed using non-standard materials which may, nevertheless, be “fit for purpose”; - Geometric design standards may need to be “relaxed” in appropriate circumstances without undue increase in risk to road users; - The deterioration of these roads is primarily driven by environmental factors wit traffic load being a lesser factor; - Environmental issues often result in increased costs; - Conventional economic analysis often cannot justify the investment of public funds in the construction and maintenance of these roads. The above characteristics challenge conventional engineering in a variety of ways which require a delicate balance to be struck between controlling both traffic and environmental deterioration at the least life cycle cost and with finely balanced risk factors whose complete removal would be too costly. In so doing, it has become necessary to adopt an “environmentally optimized” approach to design in which a variety of road environment factors must be addressed in an appropriate manner. This paper provides examples of relatively recent developments in low volume roads technology that allow such roads to be provided in a more affordable and sustainable manner than hitherto, and without incurring unmanageable risk for road users or the agencies that provide them. The paper concludes that a paradigm shift in thinking is required to move away from the conservative, and often inappropriate, approaches of the past to more progressive approaches informed by research-based evidence.
Pinard, M.; Paige-Green, P.; Hongve, J. Developments in Low Volume Roads Technology : Challenging Conventional Paradigms. (2015) 11 pp.