3. SPECIMEN PREPARATION
WE USED FULLER’S FORMULA FOR GRADING
AND PREPARED SPREADSHEET FOR THAT
ALSO.
WHERE ‘p’ is PERCENTAGE
PASSING THROUGH SIEVE
UNDER CONSIDERATION
‘D’ is LARGEST PARTICLE SIZE
‘d’ is SIEVE UNDER CONSIDERATION
‘n’ is FULLER INDEX AND TAKEN as 0.45 by
us.
5. NOTATIONS
W1, W2, W3 AND Wb ARE
WEIGHT OF COARSE
AGGREGATES, FINE
AGGREGATES, FILLER AND
BITUMEN RESPECTIVELY.
V1, V2, V3, Vb AND Vv ARE
VOLUME OF COARSE
AGGREGATES, FINE
AGGREGATES, FILLER,
BITUMEN AND AIR VOIDS
G1, G2, G3 AND Gb ARE
SPECIFIC GRAVITIES OF
COARSE AGGREGATES,
FINE AGGREGATES,
FILLER AND BITUMEN
14. OPTIMUM BITUMEN CONTENT
BITUMEN CONTENT CORRESPONDING TO
MAXIMUM MARSHALL STABILITY VALUE= 5.5%
BITUMEN CONTENT CORRESPONDING TO
MAXIMUM BULK SPECIFIC GRAVITY= 5%
BITUMEN CONTENT CORRESPONDING TO MEDIAN
(4%) OF AIR VOIDS %= 4%
AVERAGE VALUE= 4.8%
THEREFORE OPTIMUM BITUMEN CONTENT= 4.8%
15. “Engineering problems are under-defined, there are many solutions, good, bad and
indifferent. The art is to arrive at a good solution. This is a creative activity,
involving imagination, intuition and deliberate choice.”
OVE ARUP
Engineers … are not superhuman. They make mistakes in their assumptions, in their
calculations, in their conclusions. That they make mistakes is forgivable; that they
catch them is imperative. Thus it is the essence of modern engineering not only to be
able to check one’s own work but also to have one’s work checked and to be able to
check the work of others.