SAPEM Chapter 2 - Sanral

South African Pavement Engineering Manual
Chapter 2: Pavement Composition and Behaviour
observed in many African countries, where agricultural and mining output increases by an order of magnitude
through provision of new road infrastructure. Links to ports are especially important.
The 21 st century has commenced with an emphasis on:
Improvements in material science and introduction of specialist materials that provide enhanced performance
e.g., polymer modified bitumen.
An environmental focus that includes sustainable practice; minimal impact on the environment, i.e., minimising
the carbon-footprint and recycling with minimal utilisation of non-renewable resources; and, permeable
pavements to reduce run-off.
New priorities and frameworks for procurement and road delivery, including the needs of developing areas,
such as Public-Private-Partnering (PPP). See Chapter 11 for procurement and contracting.
Increases in traffic volumes have resulted in the need for increased design pavement capacities. At the
same time, design strategy has moved towards perpetual or long-life pavements. These pavements aim to
provide structural capacity for 30 to 50 years with only functional maintenance requirements. It is necessary to
adopt long-life pavements because the opportunities for maintenance and rehabilitation interventions are severely
restricted for the following reasons:
Road user costs, particularly costs relating to traffic delays, are exorbitant.
Access to the road pavement is restricted, resulting in construction being carried out at night or over
weekends.
John F Kennedy
“Building a road or highway isn’t
pretty. But it is something that
our economy needs to have!”
Section 2: History
Page 7