16. Net ultimate bearing capacity of a footing embedded in a clay stratum

1. 1. increases with depth of footing only

   
   
   

   2. increases with size of footing only

   
   
   

   3. increases with depth and size of footing

   
   
   

   4. is independent of depth and size of footing

   
   
   

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1. View Hint View Answer Discuss in Forum

   q_u = CN_c + 8DN_q + 0.5 B_γN_γ
   For clay, Φ = 0 (pure cohesive)
   ⇒ N_q = 1, N_γ = 0
   ⇒ Q_u = CN_c + γD
   ∴ Q_un = q_u – γD
   ∴ = CN_C + γD – γD = CN_c

   Correct Option: D

   q_u = CN_c + 8DN_q + 0.5 B_γN_γ
   For clay, Φ = 0 (pure cohesive)
   ⇒ N_q = 1, N_γ = 0
   ⇒ Q_u = CN_c + γD
   ∴ Q_un = q_u – γD
   ∴ = CN_C + γD – γD = CN_c

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17. Dilatancy correction is required when a strata is

1. 1. Cohesive and saturated and also had N/Value of SPT > 15

   
   
   

   2. Saturated silt/fine sand and N value of SPT < 10 after the overburden correction

   
   
   

   3. Saturated silt/fine sand and N value of SPT > 15 after the overburden correction

   
   
   

   4. Coarse sand under dry condition and N value of SPT < 10 after the overburden correction

   
   
   

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1. View Hint View Answer Discuss in Forum

   ng = 15 +	1	(N0 - 15)
   	2

   
   N₀ - SPT value after over burden pressure correction is applied.

   Correct Option: C

   ng = 15 +	1	(N0 - 15)
   	2

   
   N₀ - SPT value after over burden pressure correction is applied.

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18. A smooth rigid retaining wall moves as shown in the sketch causing the back fill material to fail. The black fill material is homogeneous and isotropic, and obeys the Mohr-Coulomb failure criterion. The major principal stress is
    

1. 1. parallel to the wall face and acting downwards

   
   
   

   2. normal to the wall face

   
   
   

   3. oblique to the wall face acting downwards

   
   
   

   4. oblique to the wall face acting upwards

   
   
   

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1. View Hint View Answer Discuss in Forum

   Retaining wall moves towards back fill ie, positive earth pressure
   ie, σ_h > σ_v.

   Correct Option: B

   Retaining wall moves towards back fill ie, positive earth pressure
   ie, σ_h > σ_v.

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19. Likelihood of general shear failure for an isolated footing in sand decrease with
    

1. 1. decreasing footing depth

   
   
   

   2. decreasing inter-granular packing of the sand

   
   
   

   3. increasing footing width

   
   
   

   4. decreasing soil grain comprehensibility

   
   
   

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1. View Hint View Answer Discuss in Forum

   decreasing inter-granular packing of the sand

   Correct Option: B

   decreasing inter-granular packing of the sand

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20. Two geometrically identical isolated footings × (linearly elastic) and Y (rigid), are loaded identically (shown alongside). The soil reactions will.
    

1. 1. be uniformly distributed for Y but not for X

   
   
   

   2. be uniformly distributed for X but not for Y

   
   
   

   3. be uniformly distributed for both X and Y

   
   
   

   4. not be uniformly distributed for both X and Y

   
   
   

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1. View Hint View Answer Discuss in Forum

   be uniformly distributed for Y but not for X

   Correct Option: A

   be uniformly distributed for Y but not for X

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