Question

Match list A with list B and select the correct answer using the codes given below the list.

List - A	List - B
A. Minimum cover	1. Ultimate moment capacity
B. Span to depth ratio	2. Durability
C. Limit state design	3. Serviceability
D. Doubly reinforced section	4. Reduction in sectional depth

1. A - 3, B - 2, C - 1, D - 4
2. A - 2, B - 3, C - 4, D - 1
3. ​A - 3, B - 2, C - 4, D - 1
4. A - 2, B - 3, C - 1, D - 4

Answer 1

Correct Answer - Option 4 : A - 2, B - 3, C - 1, D - 4

Explanation:

Minimum Cover-

(i) Concrete cover is assumed to be the first measure considered to prevent influences of aggressive elements on the reinforcement steel bars. That is why utmost cautions are needed during concrete cover thickness design and its construction.

(ii) Commonly, the thickness of concrete cover is specified based on the type of the reinforced concrete member and the environment in which the structure is constructed.

(iii) It is provided to make the structure durable.

Span to depth Ratio-

(i) In order to satisfy the serviceability limit states, a concrete structure must be serviceable and perform its intended function throughout its working life. Excessive deflection should not impair the function of the structure or be aesthetically unacceptable. So span to depth ratio has to be within the permissible limit to maintain the limit state of serviceability.

Limit state design-

(i) In limit state design the ultimate moment capacity of beam and slab can be calculated. When moment acting on the structure exceeds the ultimate moment capacity then the structure fails.

Doubly reinforced section-

(i) Due to high moment when the depth requirement is high which makes the structure uneconomical and aesthetically unpleasant then doubly reinforced section is used to decrease the depth of the section.

(ii) In doubly reinforced section Reinforcement is provided on both compression and tension side.