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Swedish circle

Used for homogeneous clay soil with = 0Applicable only for short-term analysis of clay slopes (Undrained)Calculated from moment∑ = ∑ 1 1 2 2

∑∑ ∑

Have to find center of circle /failure surface that results in lowest FS by trial and error

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Swedish circle

Stability number(안정정수)Fellenius (1927)Taylor (1937)

dcH

dcH Stability factor

(안정계수)Terzaghi and Peck (1967)

한계상태에서의 비배수전단강도와 단위중량 – 사면고의 관계

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Swedish circle

Used for homogeneous clay soil with = 0Applicable only for short-term analysis of clay slopes (Undrained)Calculated from moment equilibrium ∑ ∑∑ = ∑ 1 1 2 2

∑∑ ∑

Have to find center of circle /failure surface that results in lowest FS by trial and error

CIE3032 지반공학및실험 lecture 04 slope stability 34

Swedish circle

∑ ∑

FS = , Stability number(안정정수)Fellenius (1927)Taylor (1937)

dcH

dcH Stability factor

(안정계수)Terzaghi and Peck (1967)

한계상태에서의 비배수전단강도와 단위중량 – 사면고의 관계(Note at failure, cd = su)

CIE3032 지반공학및실험 lecture 04 slope stability 35

Swedish circle

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Swedish circle

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Swedish circle

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Swedish circle

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Ordinary method of slices

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3. Simplified Bishop’s method

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cos i iW P U

Simplified Bishop Method

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Effect of water table

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Comparison of slope stability methods

MethodForce-equilibrium Moment

Equilibriumx yOrdinary method of slices(OMS)Bishop’s simplifiedJanbu’s simplifiedCorps of EngineersLowe & KarafiathJanbu’s generalizedBishop’s rigorousSpencer’sSama’sMorgenstern-Price

NoYesYesYesYesYesYesYesYesYes

NoNoYesYesYesYesYesYesYesYes

Yes YesNoNoNoNoYes YesYesYes

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Swedish circle - Example

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