Solution Manual For Principles of Foundation
Engineering exam Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. Which property of soil primarily controls the rate at which excess
pore-water pressure dissipates during consolidation?
A. Specific gravity
B. Permeability
C. Plasticity index
D. Grain shape
Answer: B. Permeability
Rationale: Permeability determines how readily water can flow through
soil voids. During consolidation, excess pore-water pressure dissipates
as water drains from the soil, so permeability strongly influences the
rate of settlement.
2. The primary purpose of a foundation is to:
,A. Increase the weight of a structure
B. Transfer structural loads safely to the supporting soil
C. Prevent all groundwater movement
D. Eliminate soil settlement completely
Answer: B. Transfer structural loads safely to the supporting soil
Rationale: Foundations transfer structural loads to the ground while
maintaining adequate bearing capacity and controlling settlement.
Proper foundation design prevents excessive deformation and shear
failure of the supporting soil.
3. Which type of foundation is generally classified as a shallow
foundation?
A. Pile foundation
B. Drilled shaft
C. Isolated footing
D. Caisson
Answer: C. Isolated footing
Rationale: Isolated footings are shallow foundations because they
transfer loads to soil relatively close to the ground surface. Piles, drilled
shafts, and caissons are generally categorized as deep foundations.
4. The ultimate bearing capacity of a foundation refers to:
,A. The allowable load after applying all safety factors
B. The load corresponding to shear failure of the supporting soil
C. The dead load of the foundation
D. The settlement at the service-load condition
Answer: B. The load corresponding to shear failure of the supporting
soil
Rationale: Ultimate bearing capacity is the maximum pressure the soil
can theoretically sustain before a bearing-capacity failure mechanism
develops. Allowable bearing pressure is obtained by applying an
appropriate factor of safety.
5. Terzaghi's bearing-capacity equation for a strip footing includes
which three major components?
A. Cohesion, surcharge, and footing-weight terms
B. Seepage, permeability, and compaction terms
C. Moisture, density, and plasticity terms
D. Settlement, drainage, and consolidation terms
Answer: A. Cohesion, surcharge, and footing-weight terms
Rationale: Terzaghi's general bearing-capacity formulation incorporates
contributions associated with cohesion, surcharge at foundation level,
, and the soil's unit weight beneath the footing. These contributions are
represented using bearing-capacity factors.
6. For a purely cohesive soil under undrained loading, the friction
angle is commonly assumed to be:
A. 0°
B. 15°
C. 30°
D. 45°
Answer: A. 0°
Rationale: In the total-stress analysis of saturated cohesive soil under
undrained conditions, the undrained friction angle is commonly taken as
zero. The soil's undrained shear strength is therefore represented
primarily by cohesion, or undrained shear strength, 𝑐𝑢 .
7. Which soil generally has the highest permeability?
A. Clean gravel
B. Silty clay
C. Clay
D. Organic clay
Answer: A. Clean gravel
Engineering exam Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. Which property of soil primarily controls the rate at which excess
pore-water pressure dissipates during consolidation?
A. Specific gravity
B. Permeability
C. Plasticity index
D. Grain shape
Answer: B. Permeability
Rationale: Permeability determines how readily water can flow through
soil voids. During consolidation, excess pore-water pressure dissipates
as water drains from the soil, so permeability strongly influences the
rate of settlement.
2. The primary purpose of a foundation is to:
,A. Increase the weight of a structure
B. Transfer structural loads safely to the supporting soil
C. Prevent all groundwater movement
D. Eliminate soil settlement completely
Answer: B. Transfer structural loads safely to the supporting soil
Rationale: Foundations transfer structural loads to the ground while
maintaining adequate bearing capacity and controlling settlement.
Proper foundation design prevents excessive deformation and shear
failure of the supporting soil.
3. Which type of foundation is generally classified as a shallow
foundation?
A. Pile foundation
B. Drilled shaft
C. Isolated footing
D. Caisson
Answer: C. Isolated footing
Rationale: Isolated footings are shallow foundations because they
transfer loads to soil relatively close to the ground surface. Piles, drilled
shafts, and caissons are generally categorized as deep foundations.
4. The ultimate bearing capacity of a foundation refers to:
,A. The allowable load after applying all safety factors
B. The load corresponding to shear failure of the supporting soil
C. The dead load of the foundation
D. The settlement at the service-load condition
Answer: B. The load corresponding to shear failure of the supporting
soil
Rationale: Ultimate bearing capacity is the maximum pressure the soil
can theoretically sustain before a bearing-capacity failure mechanism
develops. Allowable bearing pressure is obtained by applying an
appropriate factor of safety.
5. Terzaghi's bearing-capacity equation for a strip footing includes
which three major components?
A. Cohesion, surcharge, and footing-weight terms
B. Seepage, permeability, and compaction terms
C. Moisture, density, and plasticity terms
D. Settlement, drainage, and consolidation terms
Answer: A. Cohesion, surcharge, and footing-weight terms
Rationale: Terzaghi's general bearing-capacity formulation incorporates
contributions associated with cohesion, surcharge at foundation level,
, and the soil's unit weight beneath the footing. These contributions are
represented using bearing-capacity factors.
6. For a purely cohesive soil under undrained loading, the friction
angle is commonly assumed to be:
A. 0°
B. 15°
C. 30°
D. 45°
Answer: A. 0°
Rationale: In the total-stress analysis of saturated cohesive soil under
undrained conditions, the undrained friction angle is commonly taken as
zero. The soil's undrained shear strength is therefore represented
primarily by cohesion, or undrained shear strength, 𝑐𝑢 .
7. Which soil generally has the highest permeability?
A. Clean gravel
B. Silty clay
C. Clay
D. Organic clay
Answer: A. Clean gravel
