Answer :
The suitable structural steel channel for a suspension crane supporting 5,000 lbs over a 10ft span with a factor of safety of 2 should be a C15x40 channel. Thus the correct answer is C15x40 (option d)
To determine the appropriate structural steel channel for the suspension crane, we need to calculate the required load-carrying capacity and then compare it with the given options.
1. Calculate the required load-carrying capacity:
Load = 5,000 lbs
Factor of Safety (FOS) = 2
Required Load-Carrying Capacity = Load / FOS
Required Load-Carrying Capacity = 5,000 lbs / 2
Required Load-Carrying Capacity = 2,500 lbs
2. Analyze the given options:
a. C8x11.5
b. C12x20
c. C15x33.9
d. C15x40
3. Compare the required load-carrying capacity with the given options:
C8x11.5:
Capacity = 8 (strength grade) × 11.5 (depth in inches)
Capacity ≈ 92 lbs/ft
C12x20:
Capacity = 12 (strength grade) × 20 (depth in inches)
Capacity ≈ 240 lbs/ft
C15x33.9:
Capacity = 15 (strength grade) × 33.9 (depth in inches)
Capacity ≈ 508.5 lbs/ft
C15x40:
Capacity = 15 (strength grade) × 40 (depth in inches)
Capacity ≈ 600 lbs/ft
Among the given options, the C15x40 channel has the highest load-carrying capacity (600 lbs/ft), which is suitable for the suspension crane's requirements. Therefore, the C15x40 channel should be selected for the suspension crane supporting 5,000 lbs over a 10ft span with a factor of safety of 2.Thus the correct answer is C15x40 (option d)
