7. Road Concepts illustrated - principles of topography management

Road sections act as channels ad attenuate the rain peaks, resulting in smaller pipe sizes of storm drains. Sewers and storm drains together with manholes remain shallow and, therefore, cheap. Lengths of storm drains reduce as their function is partly taken over by roads. Road sections with curbs are more durable. The expense of road filling, which may be as much 25% of the total road cost, can be avoided if the conventional raised road section is not adopted. Fill needed for regarding and earthworks is generated on-site from the road excavations rather than importing from outside. This again saves costs.

  • Road sections act as channels ad attenuate the rain peaks, resulting in smaller pipe sizes of storm drains.
  • Sewers and storm drains together with manholes remain shallow and, therefore, cheap.
  • Lengths of storm drains reduce as their function is partly taken over by roads.
  • Road sections with curbs are more durable.
  • The expense of road filling, which may be as much 25% of the total road cost, can be avoided if the conventional raised road section is not adopted.
  • Fill needed for regarding and earthworks is generated on-site from the road excavations rather than importing from outside. This again saves costs.
  • Road base and sub-base thickness can often be reduced when in excavation because the virgin ground is likely to have greater bearing capacity than fill.