Question

The use of tie plates in laced columns is:

• A. Prohibited
• B. Not Prohibited
• C. Permitted at start and end of lacing system only
• D. Permitted between two parts of the lacing

Hint:

In laced built-up columns, use tie plates only at the ends of the lacing system, as per IS 800. Their use elsewhere can hinder effective load transfer through lacing.

Answer 1

The Correct Option is C

Step 1: Understand Laced Columns.
Laced columns are built-up compression members in which individual components are connected by diagonal lacing bars. To maintain their relative positions and transfer shear forces, intermediate connectors like tie plates may be provided.
Step 2: IS Code Reference.
According to IS 800:2007 (General Construction in Steel – Code of Practice), tie plates in laced columns are: \[ \text{"Permitted only at the beginning and end of the lacing system."} \]
Step 3: Purpose of Tie Plates.
Tie plates help maintain alignment and resist shear at joints. However, their use in between the lacing is avoided to ensure proper performance and behavior of the laced system. Conclusion:
Thus, tie plates are permitted only at the start and end of the lacing system.