Lesson 2/Learning Event 1
Example: The specifications and other data for a tack coat project are as follows
L = 2.7 miles = 2.7 x 5,280 = 14,256 feet
W = 24 feet
ARB = 0.05 gal/sq yd
LF= 5 percent or 1.05
Find the number of drums of bitumen that will be needed to do this project.
SOLUTION:
= 37.65 6 38 drums
SURFACE TREATMENT
Bituminous materials and aggregate are combined in various proportions to obtain the most
satisfactory surface for a given situation, but will not add any strength to where they are applied.
Accurate estimates are required to avoid production delays from inadequate supplies. You also
want to avoid over supply and waste of materials.
The formula for estimating supplies for a single surface treatment is:
The formula for bitumen determination is:
where:
P = weight of aggregate in pounds
T = weight of aggregate in tons
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