BCE Geotechnical 2

Question 1

What is the primary purpose of a consolidation test (oedometer test) in geotechnical engineering?

Accepted Answer

Determine compressibility and rate of consolidation of cohesive soils

Answer

The oedometer test measures how much a saturated cohesive soil compresses under load and how quickly excess pore pressure dissipates.

Question 2

Which of the following best describes the coefficient of consolidation (Cv)?

Accepted Answer

Parameter combining permeability and compressibility that governs consolidation rate

Answer

Cv = k/(mv·γw), combining hydraulic conductivity and volume compressibility to describe how fast consolidation proceeds.

Question 3

A soil has a liquid limit of 60% and a plastic limit of 30%. What is the plasticity index?

Accepted Answer

30%

Answer

Plasticity Index (PI) = Liquid Limit − Plastic Limit = 60 − 30 = 30%.

Question 4

In Terzaghi's bearing capacity equation for a strip footing, which factor accounts for the depth of embedment?

Accepted Answer

Nq

Answer

Nq is the bearing capacity factor associated with the surcharge term (q = γDf), which represents the overburden pressure from footing embedment depth.

Question 5

What type of failure surface does Rankine's earth pressure theory assume?

Accepted Answer

Planar (straight line) slip surface

Answer

Rankine's theory assumes a planar failure surface inclined at 45 + φ/2 degrees from horizontal for active conditions.

BCE - Bachelor of Civil Engineering Practice Test

BCE - Bachelor of Civil Engineering Practice Test

BCE Geotechnical 2