ee
Per Cent Passing 1/4"
54
eon
»"
#10
51
eon
"
£10
16
non
»
#80
2
®
uw
#200
1
A
The correct amount of Bitumuls HRM for the above
blend is 8 per cent which, for astimating purposes,
equals .8 gallon per square yard per compacted inch
of thickness, and for batching purposes in the mix-
pot equals .8 gallon per cubic foot loose of the
aggregate blend. For sand mixes only using the coral
beach sand the correct amount of Bitumuls HRM to use
is 10 per cent which, for estimating purposes, equals
1 gallon per square yard per compacted inch of thick-
ness, and for batching purposes 1 gallon per cubic
foot loose of the coral sand.
Conclusions
If an ideal blend of aggregates is desired, this
could be achieved by blending 40 per cent of the
ledge coral of the above gradation with 40 per cent
of the coral beach sand, and with 20 per cent of the
crusher dust produced at the rock plant as a byproduct of the crushing operations of the ledge coral.
The above laboratory study clearly discloses that
the ledge coral ia perfectly satisfactory for making Bitumulis mixes in combination with the coral
beach sand, or if necessary it could be used as a
straight crusher run without the addition of sand.
The coral beach sand is unusually good and if desired, could be used exclusively for a Bitumuls
sand mix for any type of paving and would give very
satisfactory results.
On the basis of the above tests and analyses, the decision was
reached by H & N engineers that the use of Bitumuls for paving purposes at Eniwetok Atoll had many advantages and warranted thorough
study to determine the best design mix to be used in the evaluation
of the various materials proposed. As a result of this decision an
engineering expert with many years experience in the asphalt field
and a broad knowledge of the characteristics of coral aggregate when
used with asphaltic binders for pavement was selected to inspect the
test strips on Parry Island and report his findings. His conclusions
and general remarks were as follows:
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