DIGEST 2006 - Sabita

Bitumen stabilised materials:
In search of sustainable
pavement design solutions
Kim Jenkins
Professor
SANRAL Chair
University of Stellenbosch
Dr Fritz Jooste
Director
Modelling and Analysis
Systems (MAS)
Over the past two
decades many South
African pavement
engineers have become aware
of mounting pressure to
conserve the environment,
coupled with a decreasing
availability of crushed stone
material.
These two issues have prompted a
radical
re-assessment
of the manner
in which
pavement
design is being
approached in
South Africa.
(G1 material in particular, as
shown in Figure 1). However, in
the face of decreasing availability
of such material, engineers now
have to improvise and recycle
existing pavement layers, as
opposed to simply importing new
crushed stone material.
The treatment of existing
pavement layers with bituminous
materials, either in the form of
Traditionally,
pavement
design
philosophy in
South Africa
was based to a
large extent on
the assumption
of readily
available and
cost effective
crushed stone
Figure 1: Breakdown of some structure types in the TRH4
(1996) catalogue for design traffic greater than
3 msa, highlighting the strong reliance of current
design guidelines on crushed stone
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