Join 60,000+ competitive exam aspirants
As per IRC standards, minimum width of two lane carriageway with raised curbs is?
m
m
m
m
m
According to the Indian Roads Congress (IRC:73-1980) guidelines for road geometry, the minimum width for a two-lane carriageway with raised curbs is 7.5 meters. This width is designed to accommodate two lanes of 3.75 m each, which is the standard lane width for major roads in urban and constrained settings.
According to the Indian Roads Congress (IRC:73-1980) guidelines for road geometry, the minimum width for a two-lane carriageway with raised curbs is 7.5 meters. This width is designed to accommodate two lanes of 3.75 m each, which is the standard lane width for major roads in urban and constrained settings.
WtotalтАЛ=n├ЧwlтАЛ
where n=2 and wlтАЛ=3.75m
The provision of raised curbs necessitates a slight increase in the effective carriage width to account for the lateral clearance required by vehicles, particularly heavy commercial vehicles, to avoid contact with the curb face. The standard design width of 3.75 m per lane, when multiplied by two, yields the 7.5 m requirement to ensure safety and prevent lateral displacement.
The standard lane width for a National Highway or State Highway is 3.75 m.
Raised curbs are typically provided in urban areas to control drainage and define the road boundary.
IRC:73 provides the geometric design standards for rural highways in India.
Horizontal clearance from the edge of the carriageway is critical for heavy vehicles.
Improved safety for motorized traffic by preventing curb collisions
Better channelization of traffic flow in urban environments
Higher initial construction cost due to curb installation
Requires better drainage management systems (gullies/drains)
Urban and Semi-Urban arterial roads
Bridge decks with pedestrian walkways
Road sections passing through built-up areas
For roads without raised curbs, the minimum two-lane width is often considered 7.0 m.
The 5.5 m option (C) represents the width for an Intermediate Lane (one-and-a-half lane) road.
A is correct тАФ The minimum width for a two-lane carriageway with raised curbs is specified by IRC as 7.5 m.
Always distinguish between rural highways (which often use 7.0 m for two lanes) and urban/curbed roads (which require 7.5 m due to lateral clearance requirements).