Shoulders , Kerb and Divider

Shoulders:  

 

                              

Theses are the extra width provided adjacent to outer edge of the road pavement for emergency purpose called as shoulder or the portion provided along the carriageway to provide lateral support to the pavement and for giving working space for stopped vehicles. It should be strong enough to bear the weight of fully load truck in emergency purposes like breakdown of vehicles even in wet condition as well as while overtaking operations.

Typical cross section of Shoulder and other members

As per IRC recommendation minimum width of shoulder for two lane road is 2.5 m. Camber of shoulder is 0.5% stiffer than camber of carriageway subjected to a minimum of 3%.  On super elevation section camber of shoulder is same as compare of carriageway, so minimum value of super elevation is equals to camber of carriageway. 

 

Actual photograph of Shoulder and Carriageway  

Colour of shoulder should preferably the different from that of the pavement so as to be distinct also it should be rougher than the traffic lanes so that users do not use it as regular traffic lane. 

Kerb : 

A vertical sloping member along the edge of a pavement provided for supporting raised footpaths or center median is called Kerb or It is the boundary between pavement and footpath. It provides the lateral support to the pavement, strengthen and protect the pavement edges, facilitate and control drainage and present a more finished appearance.

 

Typical cross section of Kerb and Divider

Type of Kerbs :

1. Mountable type Kerb
2. Semi Barrier type Kerb
3. Barrier type Kerb

Divider :

It is also called as separator, median etc,. It separates the road traffic moving in opposite direction so that chances of head on accident can be reduce. It separates the two way traffic of reduces glare effect in night.IRC recommends the minimum width of divider 5.0 n for rural highway, which may be reduced up to 3.0 m where land id restricted. 

Actual photograph of Divider