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< prev - next > Transport and infrastructure Road building KnO 100386_Improving paths and tracks part 1 (Printable PDF)
Improved paths and tracks: Part 1
Practical Action
Most improvements to paths or tracks can be carried out by local people, with some technical
direction, as the techniques are simple and make use of locally available materials. If the
improvements will benefit mainly the local people themselves, then they may be willing to
provide their labour on a voluntary self-help basis. This will be the case particularly if they feel
that they have also been fully involved in the process of identifying and prioritising the
problems. Where the benefits are more widely spread, such as on important long-distance
paths or tracks, paid labour may be necessary.
Technical direction is necessary both to specify the measures and resources required and to
supervise the work. Technical supervision is important as, inevitably, situations will arise
where on-the-spot technical decisions are required.
Design standards
The main standards to apply to a path or track are the width and the maximum longitudinal
(along the path) gradient. It is important first to establish the type of traffic which uses, or will
use, the path. The significant factors are:
the number of users per day or hour;
whether the users are load-carriers (headloading? dimensions of load?);
whether pack animals use the path or track; and
whether any wheeled vehicles (bicycles or wheelbarrows, for example) use the path or
track?
Figure 1 gives guidelines on the cleared width of path or track to adopt in different situations.
The optimum gradient for a stable path is one that drains quickly without causing erosion.
Figure 2 gives guidelines on maximum longitudinal gradients.
The major damaging factor affecting footpaths is rainwater. The preferred cross-section of a
path or track is one that sheds rainwater rapidly from its surface and leads the water safely
away without causing erosion. The most appropriate cross-section depends on the slope of the
surrounding ground, the permeability of the soil, and the volume of surface run-off. Figure 3
gives typical cross-sections which can be adopted where a section of path or track is to be fully
reconstructed.
The camber or arched cross-section can be made by using the material from the ditches dug
on either side.
For spot improvements the standards will be applied to the improved section of the path or
track only. In the special case where a path or track is to be made accessible to new types of
traffic, for example pack animals or wheeled vehicles, the new standards will need to be
applied throughout its length.
Gradient
1 in 20
1 in 14
1 in 10
1 in 9
1 in 8
1 in 5.2
1 in 4
1 in 3
1 in 2
1 in 1.4
5%
7%
10%
11%
12%
20%
26%
36%
46%
70%
Remarks
Max. gradient for bicycles with trailers
Max. gradient for bicycles
Max gradient for animal drawn carts
Desirable max. gradient for forest roads
Desirable max. gradient for forest roads
Absolute max. gradient for forest roads
Shallow steps required
Moderate steps required
Steep steps required
Hands needed to aid assent
Note: Paths to be used by wheeled vehicles or pack animals obviously cannot have steps
Figure 2: Maximum longitudinal gradients for paths and tracks
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