Along the twisty and high angle road surface in Singapore lies a need for judicious choice of tarmac material, for paving the roads to afford a safe journey to motorists travelling within the designed speed limit of the particular stretch of road.
Specifically, high angle curvature of roads meant that more grip must be present on road cars for safe negotiation of the bends at speeds sufficient to reduce congestion on busy highways in Singapore. Doing so requires the provision, through tight regulation, of tyres with the correct rubber compound to allow maximal grip on the road during most driving conditions such as rainy days or on water-logged roads. Additionally, thread pattern of the tyres must also be carefully chosen to reduce the chance of aquaplaning on wet roads.
Besides tyres and the selection of the correct tyre width to allow for required amount of contact patch (area of tyre in contact with road), roads with high angle curvature and big bends must also be carefully constructed taking into consideration the need for traction and grip with drainage. Specifically, segments of roads requiring high centrifugal force to negotiate need road surface with grip, as well as the ability to drain rainwater at a speed appropriate to maintaining sufficient grip to cars even in the worse downpours.
However, there exists a trade-off between grip and drainage. Specifically, road surface paved with a combination of pebbles, sand, gravel and bitumen afford high level of drainage during downpours, but lack sufficient grip to afford cars a safe passage through a high curvature bend. On the other hand, roads paved with bitumen of quality allowing high grip for cars, run the distinct risk of not having sufficient drainage to afford enough grip to cars in poor weather conditions.
Hence, road design and selection of surfacing material are crucial tests of the knowledge and experience of the teams of engineers and technicians involved in each project to design and build even small segments of roads such as a 100 meter stretch of a highway. In general, for a road segment to be safe, grip and traction must be balanced with water drainage as road surface with high grip but poor drainage would likely lead to aquaplaning and accidents.
Category: materials, physics, mechanical engineering,
Tags: road safety, mechanical grip, contact patch, rubber compound, asphalt material, tarmac, bitumen, traction, drainage, aquaplaning,