Soil Stabilization Techniques

PRESENTATION BY, SRI PAVAN KUMAR.V.

DEFINITION:Chemical or mechanical treatment designed

to increase the stability of a soil mass and improve its engineering properties.

Modification of soil structure and the reduction of the moisture content of cohesive soils lead to a considerable improvement in bearing capacity. Modification of soil structure is the concept of soil stabilization.

strength improvementDust controlSoil waterproofing

Slope Failures Bridge FailuresStructural failuresThese above failures can be eliminated by

stabilizing the soil.

Shear strengthDensityPermeability.Surface Area. Atmospheric Conditions.

CompactionAltering size distribution

Drying

Compaction has following effects on the soil:

Increases densityIncreases strengthReduces permeability

Performance of soil can be greatly improved by drying in sun or oven

Combination of chemical & physical reactions.

Materials known as stabilisers:

LimeCementBitumin

Flocculation - fine particles stick together -size

distribution changes

Lime + silica + alumina

Physical reaction

cementgels

chemical reaction

Lime + clay

LIME STABILIZATION PROCEDURE.

• Pulverization and scarification• Lime content• Uniformity of mixing• Compaction• curing

Low volume road construction -base coarse & wearing coarse.

Sub grade improvement for low & high volume roads.

CEMENT STABILIZATION PROCEDURE

• Pulverization• Cement content• Moisture content• Uniformity of mixing• Compaction• Curing.

• Cement stabilised soils usually stronger than lime stabilised soils.• Similar uses to lime stabilised soils.

The factors that seem most important to control are

Surface moisture content Viscosity of the asphalt Asphalt content Uniformity of mixingAeration Compaction and curing.

GROUTING METHODS:Grouting pressures shall be sufficiently in

excess of confining overburden pressures to adequately compact the soil and fill all voids in the soil beneath the indicated areas. In no cases, however, shall the pressures be high enough to cause structural damage to the building.

Where drilling indicates the presence of small voids, grouting shall begin at ledge rock elevation and continue upward in 12 inch maximum increments.

USES:Soil stabilization by compaction grouting is to improve supporting characteristics of the silty clay sub soils, and prevent any further settlement from occurring within the area indicated on the Contract Drawings.

Preserve Vegetation MulchingHydraulic Mulch Hydroseeding Soil Binders Straw Mulch Rolled Erosion Control Products Wood Mulch

Improves the strength and durabilityStabilisation of sub-grade to increase CBRReductions in bulk dig quantities This technique is a cost effective alternative to

importing aggregates for both temporary and permanent works.

THANK YOU