Question

For a steel built-up column subjected to an axial force of 1200 kN, the lacing system is to be designed for resisting transverse shear of

• A. \( 10 \, \text{kN} \)
• B. \( 20 \, \text{kN} \)
• C. \( 30 \, \text{kN} \)
• D. \( 40 \, \text{kN} \)

Hint:

For built-up columns, the transverse shear for lacing design is typically 2.5% of the axial force as per IS 800:2007. Check the relevant code for variations (e.g., AISC uses 2% in some cases).

Answer 1

The Correct Option is C

Step 1: Understand the role of the lacing system.
In a steel built-up column, the lacing system resists transverse shear due to imperfections or eccentricities, as per IS 800:2007 (Clause 7.6.2).
Step 2: Calculate the transverse shear force.
As per IS 800:2007, the lacing system should resist a transverse shear of 2.5% of the axial force. Given axial force = 1200 kN: \[ \text{Transverse shear} = 0.025 \times 1200 \, \text{kN} = 30 \, \text{kN}. \]
Step 3: Compare with the options.
The calculated transverse shear of 30 kN matches option (3), confirming the solution.