Improving paths & tracks: Part 2
Practical Action
through these areas. Particularly useful are rafts or turnpike sections using imported
material, with or without membranes.
Path construction laid
on the membrane
Loose sand is a problem to walk across because:
it does not contain
clayey particles and
therefore does not
bind together well;
and
the sand particles are
all similar in size and
therefore tend to act
like tiny ‘marbles’,
with little interlocking
of adjacent particles.
Membrane
Edges tucked into
ground
The loose sand cannot,
therefore, be used directly
Figure 7: Turnpike with membrane at ground level
as fill material in the ‘turnpike’ method of construction. It will however be suitable if mixed
with clayey material brought to the site from elsewhere. Some granular material can also be
used in the ‘mix’ if appropriate. A little experimentation with the proportions of sand and clay
available locally will be necessary to arrive at the correct combination. Obviously, the aim
should be to use as much local sand as possible to reduce the amount of clay which must be
carried to the site.
References and further reading
Improving Paths and tracks Part 1 Practical Action Technical Brief
Improving Paths and Tracks Part 3 Practical Action Technical Brief,
Dry Stone Causeways Practical Action Technical Brief,
Rural Transport Services Beenhakker, H., with S. Carapetis and others, IT Publishing,
1989.
Roads are not Enough, Dawson, Jonathan and Ian Barwell Practical Action Publishing,1993.
Earth Roads: Their construction and maintenance, Hindson, J., revised by J. Howe and G.
Hathway, Practical Action Publshing, 1983.
Low-cost Vehicles: Options for moving people and goods, Gordon Hathway. Practical Action
Publishing, 1985.
Low-cost Load-carrying Devices: The design and manufacture of some basic transport
technologies, Ron Dennis, Practical Action Publishing,1995.
Labour-based Road Construction: A state of the art review, Paul Larcher (Ed.), Practical
Action Publishing, 1998
Road Maintenance and Regravelling (ROMAR) Using Labour-Based Methods: Handbook,
Claes-Axel Andersson et al, Practical Action Publishing, 1996,
Footpaths and Tracks: A field manual for their construction and improvement, Ron Dennis et
al, I.T. Transport Ltd., March 2002,
Upland Pathwork Construction Standards for Scotland, Upland Path Advisory Group,
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