4. Setting Time
Initial setting time is the time that
elapsed from the instance of adding water untill the pastes ceases
to behave as fluid or plastic. Whereas final setting time
referred to the time required for the cement paste to reach certain
state of hardness to sustain some load. Setting time is tested
by Vicat apparatus or Gillmore needle.
5. Compressive Strength
Compressive strength of cement is tested
by 50 mm mortar cubes made by using standard sand and cured in
a prescribed way. the cubes are tested under a compression
testing machine. The strength of cement varies with time,
therefore in general it is reported as 3 day, 7 day or 28 day
strength.
6. Heat of hydration
The heat generated during the reaction
of cement and water is known as heat of hydration. The factors
affecting heat of hydration are C3A, C2S, watercement ration,
fineness of cement and curing temperature. Conduction calorimeter
is used to test heat of hydration.
7. Loss on Ignition
A cement sample of known weight is
heated between 900  1000°C (1650  1830°F) until a constant weight
is obtained. The weight loss of the sample due to heating is then
determined. A high loss on ignition (more than 3%) indicates
prehydration and carbonation, which may be due to
inappropriate storage or adulteration.
8. Specific gravity (relative density)
Specific gravity is generally required
in mix proportioning for concrete. The particle density (measured by
excluding the air between particles) of OPC is found to be in the
range of 3.1 to 3.25 Megagram per cubic meter. The relative density
of OPC is assumed as 3.15. The density of cement is determined by Le
Chatelier apparatus.
9. Bulk Density
The bulk density can be determined by
dividing the mass of cement particles and air between particles by
the volume of cement sample. Bulk density of OPC ranges from 830 kg/cu.m
to 1650 kg/cu.m. This test can be done with the help of two beakers
having same amount of cement. The cement in one beaker is slightly
vibrated which shows a decrease in the volume.
Problem Solver^{New}
A collection of illustrated solved examples for civil
engineers. 
Moment
Distribution Calculator^{New}
Easy to use calculator for solving Indeterminate beams with
different load
Overhanging
Beam Calculator^{New}
Bending Moment & Shear Force Calculation
for Overhanging beam with different loads
Fixed Beam Calculator
Shear force and bending moment calculations for different loading
cases of Fixed beam
RC Beam Calculator^{New}
Calculate the strength of reinforced concrete beams
