Question

How much percentage increase of permissible stress is allowed when dead load, live load and wind load are considered together in working stress method?

• A. 0.5
• B. 0.33
• C. 0.4
• D. 0.6

Hint:

In working stress method, wind or seismic effects allow an increase in permissible stress to account for their short-duration nature.

Answer 1

The Correct Option is C

Step 1: Recall working stress method provisions.
In the working stress method, permissible stresses are allowed to be increased when wind or earthquake loads are considered along with dead and live loads.
Step 2: Standard increase allowed.
As per IS codes, when dead load, live load, and wind load act together, the permissible stress can be increased by 40%.
Step 3: Convert percentage to decimal form.
\[ 40% = 0.4 \]
Step 4: Conclusion.
Hence, the correct answer is (C) 0.4.