Practice Test GeeksBCE - Bachelor of Civil Engineering Practice Test
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Geotechnical Flashcards

7 cards from real BCE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

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  1. What is the primary purpose of a geosynthetic reinforcement layer placed within a compacted fill embankment?

    Answer: Provide tensile resistance to improve embankment stability and reduce lateral spreading

    Geogrid or geotextile reinforcement carries tensile stress that soil cannot, improving overall embankment stability and controlling lateral deformation at the base.

  2. Which slope stability method satisfies both force and moment equilibrium for each slice and is considered the most rigorous?

    Answer: Spencer's Method

    Spencer's method assumes a constant interslice force inclination and satisfies both overall moment and force equilibrium, making it one of the most complete methods.

  3. A soil profile shows SPT N-values of 2-4 in the upper 5 m followed by N > 50 below. What foundation type is most appropriate for a heavily loaded column?

    Answer: Deep pile foundation driven to the dense layer

    N = 2–4 indicates very soft to soft ground incapable of supporting heavy loads; deep piles driven to the dense bearing stratum (N > 50) are required.

  4. What is the definition of the overconsolidation ratio (OCR)?

    Answer: Ratio of preconsolidation pressure to current vertical effective stress

    OCR = σ'p / σ'v0; OCR = 1 means normally consolidated, OCR > 1 means overconsolidated, indicating the soil has experienced higher stresses in its past.

  5. During a triaxial CD test on dense sand, what typically occurs to pore pressure and volume as shear strain increases past peak?

    Answer: Negative pore pressure develops and volume increases (dilative)

    Dense sand dilates (expands) during shear in a drained test; in undrained conditions this would manifest as negative (suction) pore pressures.

  6. What is the role of the compression index (Cc) in settlement calculations for normally consolidated clay?

    Answer: Quantifies the slope of the e-log σ'v curve used to calculate primary consolidation settlement magnitude

    Cc is the slope of the virgin compression line on an e vs. log σ'v plot; it is used in ΔH = Cc·H/(1+e0)·log(σ'f/σ'0) to compute consolidation settlement.

  7. Which of the following ground improvement techniques uses vertical drains to accelerate consolidation of soft clay under an embankment?

    Answer: Stone columns with prefabricated vertical drains (PVDs)

    Prefabricated vertical drains (band drains) shorten the drainage path from the full layer thickness to the drain spacing, dramatically reducing time for consolidation under surcharge loading.