Pavement Design Catalogue - LGED

The Pavement Design Catalogue also provides guidelines for Road Junction, Road
Intersection and Road Widening for Bus Stop and rural traffic stand.
The Pavement Design Catalogue contains Pavement cross-sections for Upazila Roads
and Union Roads (previously called FRB and Rural Roads) along with shoulder and
drainage treatment in Hilly areas.
The Pavement Design Catalogue provides important guidelines for Gradients and Super
Elevation for longitudinal profile of roads and extra width of pavement required at
horizontal curves.
The Pavement Design Catalogue also provides sample protective measures to road
embankment venerable to erosion due to wave action of floodwater in Char and Haor
areas.
GEOMETRIC DESIGN CRITERIA OF UPAZILA ROAD AND UNION ROAD
1. Gradients
Gradient is the longitudinal slope of a road. The following gradients for Upazila Roads
and Union Roads tentatively recommended:
Table-1
Gradients
Terrain Ruling grade (Maximum) Limiting grade (Maximum)
Plains 1 in 30 1 in 20
Hills 1 in 20 1 in 15
a. Ruling gradient: This gradient is the slope of the road, which is adopted in road
design and calculations of cuts and fills. This gradient is decided in such ways that
slow moving and fast moving, both types of traffic can easily negotiate over this
slope.
b. Limiting gradient: This gradient may be used, where topography of a place compels
this course or where the adoption of gentler gradients would add enormously to the
cost. In such cases, the lengths of the continuous grade line at a grade steeper than
the ruling gradient should be limited as far as possible. In hills where limiting gradients
have to be used rather frequently, it is important to separate such stretches by
providing stretches of level road on easier grades.
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