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The road in question is a 54.4km
road with 312 horizontal curves and more than 200
vertical curves. The road joins two villages in the
southwestern corner of Lesotho. The existing road is
very narrow with many sharp curves and steep
gradients. The new road is to be a Class B standard
with a gravel wearing course on a subbase layer.
“This road posed a myriad of challenges for us. For
both environmental and geotechnical reasons, cut and
fill were to be minimized. The existing road has to be
used during construction as we cannot create any
temporary detours, and all along the route there are
villages, houses and even cemeteries”, says Donovan.
The road was commissioned by the Lesotho Government as
part of its 5-year Road Rehabilitation and Maintenance
Project and financed by the International Development
Association of the World Bank, the European Union and
other donors. This program is one of the key aspects
of a strategy to alleviate poverty in the region by
developing and maintaining infrastructure
“I spoke to Vincent Bester at Knowledge Base and we
decided to give Civil Designer 6.2 Beta version a shot
at getting the job done. The new version automatically
designed the Super Elevation for all the 312
horizontal curves. I was able to complete this job in
approximately three months on my own, with some
assistance on the geotechnical and hydrology side”,
says Donovan.
“What makes this achievement even more remarkable is
that Dawid du Toit of Knowledge Base customised the
program for me as we went along”, says Donovan.
“Having this kind of support is absolutely amazing, it
is unheard of in the industry”.
“I had to keep in mind that the road is going to be
constructed using local labour a case of a high-tech
design for a low-tech construction. There are
approximately 150 watercourse or drainage line
crossings along the route.
There are 7000m2 of Reinforced Earth type retaining
structures and, in some cases, up to 17m fill
embankments. The bridges are to be constructed using
Armco type culverts, as you can't easily get
reinforced concrete to the sites”, says Donovan.
“We were able to put the terrain drawing in the
background which helped a lot when we encountered
houses or cemeteries. Due to these constraints, as
well as the very steep mountain slopes, many shifts in
alignment had to be checked it was so sensitive - and
the program did the rest”, says Donovan. “Using Civil
Designer saved me at least a couple of months in
iterations, in fact I wouldn't have been able to
finish on time without the software”.
“This road will mean a lot to the people of the area
when it is complete. It will not only cut the travel
time by more than half it currently takes more than
two hours to travel the 50kms it will open up all
sorts of opportunities for tourism and trade”, says
Donovan.
“The existing road is a narrow 3 - 4m track running up
and down the mountains, around incredibly tight
corners in some the radius is just 15m, and now they
will have a road that is more than double the width
and vastly improved alignments”.
“This is a great engineering project to have been
involved in, and having superb software and a direct
line into the developer made for great teamwork. Civil
Designer certainly helped me in this project”, says a
proud Donovan.
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