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< prev - next > Transport and infrastructure Road building KnO 100388_Improving paths and tracks part 3 (Printable PDF)
IMPROVED PATHS AND
TRACKS PART 3
The improvement of paths and tracks in steep, hilly, and mountainous terrain presents a
particular challenge. It is precisely in these areas, of course, that roads are few and rural
communities depend heavily on paths and tracks for many of their journeys. So, improving
paths and tracks in steep terrain can bring significant benefits to local people by making them
both easier and safer to use. The main problem in steep areas is that paths and tracks can
become slippery and eroded as a result of rainfall, making them dangerous to negotiate. This
technical brief examines ways of improving paths and tracks by: reducing gradients by
realigning steep sections; constructing steps on steep sections; and combating erosion by
constructing water bars.
Reducing gradients
The most obvious method of improving a very steep section of a path or track is to reduce its
gradient by choosing a new alignment. This can be achieved by constructing a path which
ascends a slope diagonally, either as an oblique path or through a series of zig-zags, rather
than directly up the slope.
A new route can be selected by following this basic procedure:
Decide on the maximum desirable gradient.
Mark this on the ground using pegs and a clinometer or other angle-measuring device.
Walk the route to inspect for obstacles and hazards.
Desirable maximum gradient
The desirable maximum gradient is one that users of the path or track can negotiate without
major difficulty. For a pedestrian, the desirable maximum gradient is 12 per cent or about 1
in 8. For wheeled vehicles and heavily loaded porters, the desirable maximum gradient is
lower. General guidelines are given in Figure 1.
User
Bicycles with trailers
Bicycles
7%
Animal-drawn carts
Loaded porters
Pedestrians
Pack animals
Desirable
maximum gradient
5%
8%
10%
12%
12%
1 in 20
1 in 14
1 in 12
1 in 10
1 in 8
1 in 8
Figure 1: Desirable Maximum Longitudinal Gradients for Paths and Tracks
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