2.1.3. Coarse aggregate
Crushed gravels with a nominal maximum size of 10 mm were
used as the coarse aggregate. Water absorption of the coarse aggregates
used in this study under SSD condition was measured by
immersion in water for 24 h, followed by removing excess surface
water with wet cloth after they were moved out of water. At the
time when there was no free water on the surface, aggregates
were assumed to be under the SSD condition. The sampled aggregates
with saturated water under the surface-dried condition
were weighed and recorded as mSSD. After 24 h oven-drying at a
temperature of 105 C, aggregates were weighed and recorded as
mOD. The SSD water absorption was calculated by the formula of
(mSSD mOD)/mOD. The volume of the sampled aggregates under
the SSD condition was measured by using the water displacement
method and recorded as vSSD. The SSD density of gravels was
calculated by the formula of mSSD/vSSD. The results of SSD water
absorption and SSD density of gravels are presented in Table 1.