Question

In limit state design of reinforced concrete, deflection is computed by using

• A. initial tangent modulus
• B. secant modulus
• C. tangent modulus
• D. short-and long-term values of Young's modulus

Answer 1

The correct option is D short-and long-term values of Young's modulus

The short term deflections may be calculated using methods for elastic deflections using the short term modulus of elasticity of concrete $E_c$ and effective moment of inertia.
For long term deflections, the long term modulus
$E_{ce}=\frac{E_c}{1+\theta }$ is used where $\theta$ is creep coefficient