Question

If two foundations, one narrow and another wide, are resting on a bed of sand carrying the same intensity of load per unit area, then which one is likely to fail early?

• A. Narrow foundation
• B. Wider foundation
• C. Both will fail simultaneously
• D. Difficult to judge since other conditions are unknown

Hint:

- In sand, narrow foundations fail earlier due to higher stress concentration. - Wider foundations distribute load, reducing settlement and failure risk.

Answer 1

The Correct Option is A

Step 1: Understanding soil pressure distribution. - In sand, the bearing capacity depends on width of the foundation. - A wider foundation spreads load over a larger area, leading to lower settlement. Step 2: Effect of width on failure. - Narrow foundations lead to higher stress concentration on the soil, causing higher settlement and failure earlier. - Wider foundations distribute the load more effectively, reducing failure chances. Thus, the correct answer is (A) Narrow foundation.