Structural Analysis - Study Mode

[#56] When a uniformly distributed load, longer than the span of the girder, moves from left to right, then the maximum bending moment at mid section of span occurs when the uniformly distributed load occupies
Correct Answer

(D) Whole span

[#57] Degree of static indeterminacy of a rigid-jointed plane frame having 15 members, 3 reaction components and 14 joints is
Correct Answer

(C) 6

Explanation

Solution: To determine the degree of static indeterminacy (Ds) for a rigid-jointed plane frame, use the formula:

Ds = (3m + R) - (3j + A) where: m = number of members, R = number of reaction components, j = number of joints, A = number of internal hinges (A = 0 in this case). Given: m = 15 (members), R = 3 (reaction components), j = 14 (joints), A = 0 (no internal hinges). Substitute these values into the formula: Ds = (3 * 15 + 3) - (3 * 14 + 0) Ds = (45 + 3) - (42) Ds = 48 - 42 = 6 Thus, the degree of static indeterminacy is 6.

[#58] For heavily reinforced concrete member, the nominal maximum size of the aggregates should be restricted to
Correct Answer

(C) Smaller of A and B

Explanation

Solution: The nominal maximum size of the aggregates in heavily reinforced concrete members is determined to ensure proper compaction and minimal voids in the structure. 1. To avoid interference with the reinforcement, the size of the aggregate should be restricted to 5 mm less than the minimum clear distance between the main bars. 2. Similarly, to maintain adequate cover, the size of the aggregate should also be restricted to 5 mm less than the minimum cover to the reinforcement. 3. Therefore, the nominal maximum size of the aggregates should be the smaller of these two criteria to satisfy both conditions. This ensures proper placement and compaction of the concrete mix around the reinforcement.

[#59] The fixed support in a real beam becomes in the conjugate beam a
Correct Answer

(D) Free end

[#60] When a series of wheel loads crosses a simply supported girder, the maximum bending moment under any given wheel load occurs when
Correct Answer

(B) The centre of span is midway between the centre of gravity of the load system and the wheel load under consideration