REINFORCED EARTH RETAINING WALLS & SLOPES SOUMYA S GROUND IMPROVEMENT TECHNIQUES
• Important in highway construction as their use reduces the required width of new right-of-way and facilitates construction within existing limited right-of-way.
Reinforced embankments over soft foundations
• A cost-effective alternative to traditional techniques for constructing earthen embankments over low strength foundations
Load Transfer Mechanism The flexible reinforcement interacts frictionally with the soil
resisting the shear stresses in the soil mass
The shear stress at the interface of the soil and the reinforcement generates strains in the reinforcement and a tensile force is mobilised in the reinforcement
If this tensile force exceeds the tensile capacity of the reinforcement, rupture failure occurs – Tensile failure
If deformations are high or if the interface is smooth, it is likely that a slip occurs between the soil and reinforcement – Pullout Failure
For stability, Tensile failure and Pullout failure to be examined
Principles• If a vertical stress sv is applied on a soil element, it undergoes
a vertical compression (dv) associated with a lateral deformation (dh).
• If a reinforcement is added to the soil in the form of horizontal layers, the soil element will be restrained against lateral deformation as it acted by a lateral force.
sv
dh = 0 with reinforcement
Reinforcement
sv
dv
dh
• The lateral force required for zero lateral deflection is equal to the lateral earth pressure at rest, ie K0. δv
• The lateral force required to keep the element in limiting equilibrium is equal to Ka. δv.
ie (δh)min = Ka. δv
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Facing Panels
• Panel Thickness -140, 160 and 180mm• When maximum wall height is 8m, use 140mm thick panel.
Otherwise use 160mm thick panel.