1.To determine the modulus of rupture, the size of test specimen used is
150 x150 x700 mm
2.The property of fresh concrete, in which the water in the mix tends to rise to the
surface while placing and compacting, is called bleeding
3. Lean mixes bleed less as compared to rich ones,
4.The property of fresh concrete, in which the water in the mix tends to rise to the
surface while placing and compacting, is called segregation
5. Workability of concrete is directly proportional to grading of the aggregate
6. Workability of concrete is inversely proportional to time of transit
7.Approximate value of shrinkage strain in concrete, is 0.0003
8.Air entrapment in the concrete increases workability
9.The relation between modulus of rupture fcr, splitting strength fcs and direct tensile strength fct, is given by
10.The approximate value of the ratio between direct tensile strength and flexural
strength is 0.5
11.Strength of concrete increases with increase in fineness of cement
12.The relation between modulus of rupture fcr and characteristic strength of concrete fck is given by
13.The compressive strength of 100 mm cube as compared to 150 mm cube is always more
14.According to IS : 456 -1978, the modulus of elasticity of concrete Ec (in N/mm2) can be taken as
15.Increase in the moisture content in concrete reduces the strength
16.As compared to ordinary portland cement, use of pozzuolanic cement
increases shrinkage
17.Admixtures which cause early setting, and hardening of concrete are called
accelerators
18.The most commonly used admixture which prolongs the setting and hardening time is gypsum
19.The percentage of voids in cement is approximately 40%
20.The strength of concrete after one year as compared to 28 days strength is about 20 to 25% more
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