CIE3032 지반공학및실험 lecture 03 lateral earth pressure 1

LECTURE 03

Lateral earth pressure

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 2

Coulomb’s earth pressure theory

Developed by Coulomb (1776)

Oldest earth pressure theory

Assumed failure surface is plane

Based on force equilibrium

Wall friction, inclined backfill can be taken into consideration

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 3

Coulomb’s active earth pressure

Law of sines

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 4

Coulomb’s active earth pressure

Pa dependent on βHave to find critical β that results in largest Pa

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 5

Coulomb’s active earth pressure

If α = 0°, θ = 0°, δ = 0°Ka (Coulomb) = Ka (Rankine)

β = 45° + Φ/2

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 6

Graphic solution for Coulomb’s active earth pressure: Culmann (1875)

Culman’s method can account for irregularity in geometry of backfill and surcharge load

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 7

Coulomb’s active earth pressure

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Coulomb’s passive earth pressure

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Active earth pressure with earthquake forces

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 10

Coulomb’s passive earth pressure

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 11

Common types of retaining walls

CIE3032 지반공학및실험 lecture 03 lateral earth pressure 12

Common types of retaining walls

Mechanically stabilized earth walls