They were tasked with redesigning a bitumen tank for road construction.
A second stylistic distinction was in the frequency of whorls with bitumen paint.
Each grid enclosed a 2-m section of the bitumen road along the top of the dam wall.
Certain petroleum fractions enter into this broad definition together with certain other complex materials such as shale, bitumen, pitch and even coal or coal derivatives.
The material did, however, provide good riding quality for rather longer than a standard bitumen macadam surfacing, but at a higher first cost.
This aggregate can be used in lightweight insulating concrete and can also be waterproofed with bitumen for use on flat roofs.
The bitumen felt used for window safes on this housing estate which has been found to be unsatisfactory has been almost entirely replaced.
It also includes the bitumen which has to be imported and, therefore, paid for.
