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CIE3032 지반공학및실험 lecture 03 lateral earth pressure 1

LECTURE 03

Lateral earth pressure

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 2

Curved failure surface

Shear forces that develop at the wall-soil interface causes the failure surface to become curved

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 3

Log-spiral

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 4

Rankine zone

Radial shear zone

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 5

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 6

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 7

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Additional concerns

Effect of water table

Effect of surcharge

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Calculation of passive earth pressure

qKp

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 10

Failure modes

Overturning

Sliding

Slope failure

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Braced cuts (excavation)

Provides temporary support during excavationA typical braced cut consists of sheet piles, wales, and strutsNeed to design the structural elements / spacing / intervalNeed to know the lateral earth pressure

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Earth pressures

Difference between failure modes of retaining walls and braced excavation: Failure as a single unit (simultaneous) vs. Progressive failureEmpirical earth pressure (Peck, 1969)

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 13

Braced cuts (excavation)

Calculation for the strut load: assume struts are connected by hinges except for top and bottom struts (fixed)

Example 14.2