CEE 434 GEOTECHNICAL DESIGN FALL 2008

RETAINING WALLS – PART I CEE 434 GEOTECHNICAL DESIGN FALL 2008

Why?

Applications Do not go where the path may lead, go instead where there is no path and leave a trail.“-Ralph Waldo Emerso

Tie rod Anchor Sheet pile Permanent / Temporary Retaining Structures Cantilever retaining wall Braced excavation Anchored sheet pile From: N. Sivakugan

Additional Applications Gravity Retaining wall Soil nailing Reinforced earth wall From: N. Sivakugan

Sheet Pile Walls From: N. Sivakugan

geosynthetics Mechanically Stabilized Earth (MSE) Walls Reinforced earth wallsare increasingly becoming popular. From: N. Sivakugan

Crib Walls filled with soil Good drainage & allow plant growth. Looks good. Interlocking stretchers and headers From: N. Sivakugan

Active/Passive Earth Pressures Wall moves away from soil Wall moves towards soil A B smooth wall Granular Soils From: N. Sivakugan

h’ Passive state Active state K0 state Wall movement (not to scale) From: N. Sivakugan

 failure envelope Initially (K0 state) Failure (Active state)  decreasing h’ Active Earth Pressure - in granular soils As the wall moves away from the soil, v’ active earth pressure = pa From: N. Sivakugan

 failure envelope Initially (K0 state) Failure (Active state)  increasing h’ Passive Earth Pressure - in granular soils As the wall moves towards the soil, passive earth pressure v’ = pa From: N. Sivakugan

Rankine vs. Coulomb Theory Source: B.M. Das

Coulomb: Active Case Source: B.M. Das

Coulomb: Passive Case Source: B.M. das

CEE 434 GEOTECHNICAL DESIGN FALL 2008