The 'creep coefficient' φ for concrete (IS 456) is defined as the ratio of:
Choose the correct answer
Ultimate strain / yield strain
Creep strain / elastic strain under the same sustained stress — IS 456 Table 2 gives φ=1.6–2.2 depending on age
Drying shrinkage / thermal strain
Deflection at service / deflection at ultimate
Correct Answer
B. Creep strain / elastic strain under the same sustained stress — IS 456 Table 2 gives φ=1.6–2.2 depending on age
Why is this the answer?
Creep coefficient φ = creep strain / elastic strain (all under sustained load at long term). IS 456 Table 2: φ depends on age of loading: 28-day loading φ = 1.6 (humid) to 2.2 (arid); 7-day: higher; 1-year: lower. Total strain under sustained load = elastic strain × (1+φ). For pre-stressed concrete: creep loss = E_s × ε_creep = important. Effective modulus: E_eff = Ec/(1+φ) for long-term.
Related RCC MCQs
More solved RCC questions for AE/JE Civil Engineering exams.
- The 'ductility' of RC structures is improved under earthquake loading by:
- For a circular RC water tank with rigid base, the hoop tension is maximum at:
- The 'end block' in a post-tensioned member is specially designed for:
- A 'shear wall' in a multi-storey RC building acts as:
- The 'minimum clear cover' for reinforcement in a RCC beam in severe exposure (IS 456) is:
- The 'torsion' in RC beams is resisted by:
Practice more Civil Engineering questions
This MCQ belongs to JE Level Premium Test Series. Full tests include timed attempts, rank comparison and subject-wise analysis.