Civil Engineering MCQs

2965 MCQs  (Page 40 of 297)

According to IS : 456 -1978, the modulus of elasticity of concrete Ec (in N/mm2) can be taken as______________?
A. Ec = = 5700
B. Ec = = 570
C. Ec = = 5700fck
D. Ec = where fck n/mm2 = 700 is the characteristic strength in
Admixtures which cause early setting, and hardening of concrete are called_______________?
A. Workability admixtures
B. Accelerators
C. Retarders
D. Air entraining agents
Increase in the moisture content in concrete_________________?
A. Reduces the strength
B. Increases the strength
C. Does not change the strength
D. All of the above
Air entrainment in the concrete increases________________?
A. Workability
B. Strength
C. The effects of temperature variations
D. The unit weight
Workability of concrete is inversely pro¬portional to______________?
A. Time of transit
B. ‘vater-cement ratio
C. The air in the mix
D. Size of aggregate