8차시 Stress in a soil mass (지중응력)1 -...
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CIE 3008 lecture 04 stresses in a soil mass 1 lecture 04 stress in a soil mass
Transcript of 8차시 Stress in a soil mass (지중응력)1 -...
CIE 3008 lecture 04 stresses in a soil mass 1
lecture 04stress in a soil mass
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Why do we need to know the stress (strain)?
Stress < StrengthRecall structural engineering (Allowable stress design)
Settlement (deformation) < Allowable
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Outline
• Stress and strain – a review• Components of stress and strain• Calculating stress (strain) on an arbitrary plane –
Mohr circle• Stress – strain relationship
• Distribution of vertical stresses under external loading• Point load• Line load• Circular load• Rectangular load• Empirical stress distribution estimation
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Stress Components
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Calculating stress – strain on an arbitrary plane – Mohr circle
σvσh
σv σy σ1
σh σx σ3
Sign Convention:Normal Stress+ Compression
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Normal and shear stresses – Mohr circle
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Normal and shear stresses – Mohr circle
Sign Convention:Normal Stress+ Compression
Shear Stress+ Clock-wise
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Normal and shear stresses – Mohr circle
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Mohr Circle – Change in shape
σvσh
σv
σh
∆σv
∆σv
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Mohr Circle – Change in shape
σ1σ3
σv
σh
If σv > σh
σv,
σh,
Sign Convention:Normal Stress+ Compression
Shear Stress+ Clock-wise
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Mohr Circle - Example
The soil sample is subjected to equal pressure of 10 kPa. Draw the Mohr circle.
The axial stress is increased to 50 kPa. Draw the Mohr circle.
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A shear stress of 10 kPa is applied at the vertical and horizontal boundaries. Plot the Mohr circle.
Mohr Circle - Example
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State of Stress – Mohr Circle - Pole Method
σ kPa)
kPa)
계산순서:1. 기준면선택2. Pole (극점) 계산3. 구하고자하는면도시응력계산
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State of Stress – Mohr Circle - Pole Method
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State of Stress – Mohr Circle - Pole Method
