Estimation of immediate settlement of foundation based on theory of elasticity is most appropriate for footing resting on
- Asand
- Bgravel
- CclayCorrect
- Dnone of these
Solution
Concept
Immediate Settlement of Foundations
Formula
Si = q × B × (1 - ν²) × If / Es
Step-by-step solution
1. Identify the given parameters: net pressure (q), width (B), Poisson's ratio (ν), influence factor (If), and Elastic modulus (Es). 2. Substitute the values into the elastic settlement formula: Si = q × B × (1 - ν²) × If / Es 3. Solve for immediate settlement (Si).
Explanation
Immediate settlement occurs right after load application without volume change, caused by lateral soil deformation. Because saturated clay behaves as an elastic, undrained material during rapid loading, theory of elasticity equations are most appropriately used to estimate its immediate settlement.
Shortcut
Remember: Elasticity = Clay (E-C: Elastic Clays). Elasticity theory assumes constant volume deformation (undrained state), which is characteristic of saturated clay during immediate loading.
Common mistake
Many students incorrectly select sand because immediate (elastic) settlement is commonly associated with cohensionless soils in general practice, forgetting that elastic theory equations specifically assume an undrained, constant-volume condition that best models the immediate response of saturated clay.
Correct answer: C) clay