Answer:
To design the column, we need to calculate the maximum compressive stress that the column can withstand.
Euler's formula states that the critical compressive stress is given by:
Pcr = (π² * E * I) / L²
where:
Pcr = critical compressive load
E = modulus of elasticity of steel
I = moment of inertia of the cross-sectional area of the column
L = effective length of the column
From the AISC steel manual, we can find the properties of a W14x74 beam:
- Area (A) = 21.8 in²
- Moment of inertia (I) = 735 in⁴
- Modulus of elasticity (E) = 29,000 ksi (kips/in²)
First, we need to calculate the effective length factor, K, for the column. Since the ends of the column are pin-connected, K = 1.0.
Next, we can calculate the critical load:
Pcr = (π² * 29,000 ksi * 735 in⁴) / (34 ft * 12 in/ft)²
Pcr = 859.6 kips
To find the maximum compressive stress, we divide the axial load by the cross-sectional area of the column:
σmax = (2.5 * 350 kips) / (21.8 in²)
σmax = 45.36 ksi
Finally, we check if the maximum stress is less than the allowable stress for the material. From the AISC steel manual, the allowable stress for a W14x74 column is 50 ksi. Since σmax is less than 50 ksi, the design is safe.
Therefore, a W14x74 structural steel wide-flange column is suitable for this application with pin-connected ends, a length of 34 ft, and a factor of safety of 2.5 to support an axial load of 350 kips.
Step-by-step explanation: