DIGEST 2006 - Sabita

• Fewer roller passes needed to
achieve compaction;
• Better and more consistent
density;
• Improved permeability and
thus more base protection;
• Less cold weather risk;
• Better for handwork;
• More durability and a longer
life.
The disadvantages are:
• Suitable only for light traffic;
• It costs more (due to higher
bitumen content). OH
HORRORS!
BUT IT WORKS. So decide for
yourself whether you can afford it
or not.
Now, let me get on to Cape Town's
Colto Coarse wearing course,
paved 40mm thick, but using a
massive 26.5mm max size stone.
When I bounced this mix design
off Bill Pine of Bailey Method
research fame, his reaction was
“Ha, ha, ha, ha, ha. Good luck to
them!"
On second thoughts, maybe I've
been confrontational enough for
one year, so I will save it for next
year's Digest.
Acknowledgements
Julian Wise gratefully acknowledges
the inputs of Bob Kingdon,
Carl van der Merwe and Brian
Roussouw.
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