PHASE II REPORT - Caltrans

Both systems were correctly defined by this test as quick set; the aggregate effect was clearly
distinguished. Compaction did consolidate the surface to some extent but an analysis of the
data indicates that there is no significant difference between the compacted and non-compacted
specimens and as a result compaction is not recommended. This is illustrated in Figure 4.29.
wet Loss g
300
250
200
150
100
50
0
Figure 4.29: Effect of Compaction on M2 Mixes (Wet Loss Method)
4.2.4 Effect of Tack Coat
Effect of Compaction Wet Loss at 1 Hour Cure
M2a Mix M2b
(60 Min Cure at 70°F (25°C) 70% Humidity)
Tack coat was applied on the metal base using a brush. The base plate was covered with a
thin, even coat of emulsion. The tack coat was allowed to dry to the touch. As illustrated in
Figure 4.30, the tack seemed to reduce losses perhaps by holding the sample firmly and
preventing shear at the base.
66
Not compacted
Compacted