What does USCS stand for in soil classification?

Unified Soil Classification System

True or False: Coarse-grained soils have more than 50% retained on No. 200 sieve.

True

The void ratio formula is e = _____/Vs

Vv

Which represents the degree of saturation formula?
A) S = Vw/Vt × 100%
B) S = Vw/Vv × 100%
C) S = Vv/Vt × 100%
D) S = Vs/Vv × 100%

B) S = Vw/Vv × 100%

What is the water content at liquid limit called?

The water content where soil transitions from plastic to liquid state

Fill in the blank: PI = _____ - PL

LL

True or False: Standard Proctor compactive effort is 56,000 ft-lb/ft³.

False. Standard Proctor is 12,400 ft-lb/ft³. Modified Proctor is 56,000 ft-lb/ft³.

What principle states that σ' = σ - u?

Effective stress principle

In consolidation, what does OCR represent?
A) Overall Compression Ratio
B) Optimum Consolidation Rate
C) Overconsolidation Ratio
D) Original Compression Range

C) Overconsolidation Ratio

What does Cc represent in consolidation calculations?

Compression index

True or False: For normally consolidated clay, OCR equals 1.

True

The Mohr-Coulomb failure criterion is τf = c' + σ' tan _____

Φ'

Which triaxial test allows drainage during both consolidation and shearing?
A) UU test
B) CU test
C) CD test
D) UC test

C) CD test

What does Ka represent in earth pressure theory?

Active earth pressure coefficient

Fill in the blank: K₀ = 1 - sin _____ for normally consolidated soils

Φ'

True or False: Passive earth pressure occurs when wall moves toward soil.

True

What is the factor of safety for bearing capacity typically?
A) 1.5-2.0
B) 2.5-3.0
C) 3.5-4.0
D) 4.5-5.0

B) 2.5-3.0

In Terzaghi's bearing capacity equation, what does Nc represent?

Bearing capacity factor for cohesion

For φ' = 0, what is the value of Nc?

5.7 for strip footings

True or False: Group efficiency for end-bearing piles approaches 1.0.

True

What happens to unit weight below the water table in effective stress calculations?

Use submerged (buoyant) unit weight γ'

Which soil activity classification has A > 1.25?
A) Inactive
B) Normal
C) Active
D) Highly active

C) Active

For infinite slope analysis, what is FS when c' = 0?

FS = tan φ' / tan β

True or False: Time factor Tv = cvt/Hdr²

True

What drainage path length is used for double drainage conditions?

H/2

In slope stability, what does β represent in infinite slope analysis?
A) Friction angle
B) Slope angle from horizontal
C) Cohesion angle
D) Water pressure angle

B) Slope angle from horizontal