WELCOMEWELCOME

NEW TECHNIQUES OF NEW TECHNIQUES OF EROSION CONTROLS ON HILL EROSION CONTROLS ON HILL

ROADSROADS

GUIDED BY

LECT. MANJU.P.MDEPARTMENT OF CIVIL ENGINEERING

PRESENTED BY

Lekshmi priya.mS7,CIVIL ENGGRoll Number:31

INTRODUCTIONINTRODUCTION

Transportation contributes all round Transportation contributes all round development of a country and hence development of a country and hence plays a vital rate towards its progress. If plays a vital rate towards its progress. If the highways are not properly located the highways are not properly located and may contribute sediments to and may contribute sediments to streams. The control of soil and water streams. The control of soil and water is basic to the protection of the road is basic to the protection of the road structure and therefore highway design, structure and therefore highway design, construction and maintenance must be construction and maintenance must be continually evaluated to minimize continually evaluated to minimize erosion and sedimentation problemserosion and sedimentation problems

MECHANISM OF SURFACE MECHANISM OF SURFACE EROSIONEROSION

Rain drops hit the slope surfaceRain drops hit the slope surface

Impact of raindrop detaches the Impact of raindrop detaches the particle of soilparticle of soil

The runoff water flowing on slope The runoff water flowing on slope surface transports the detached surface transports the detached particle and may also contribute particle and may also contribute to furtherto further detachmentdetachment

TYPES OF EROSIONTYPES OF EROSION

WIND EROSIONWIND EROSION

RAIN EROSIONRAIN EROSION

WIND EROSIONWIND EROSION

Exposed slope of non-Exposed slope of non-cohesive loose and dry soilcohesive loose and dry soil

Lack of shelter from windLack of shelter from wind

Exposed surface with out any Exposed surface with out any protectionprotection

FACTORS CONTROLLING FACTORS CONTROLLING WIND EROSIONWIND EROSION

Wind velocityWind velocity

Particle size of the material exposed Particle size of the material exposed to windto wind

Moisture content of soilMoisture content of soil

Vegetative coverVegetative cover

RAIN EROSIONRAIN EROSIONRain erosion is phenomenon of transporting of Rain erosion is phenomenon of transporting of soil particle due to water action, the influencing soil particle due to water action, the influencing factors for rain water erosion arefactors for rain water erosion are

Potential of flowing water for initiating particle Potential of flowing water for initiating particle detachment detachment

Physical features ie topography, gradient, Physical features ie topography, gradient, embankment slope etcembankment slope etc

Soil erodibility governed by clay content, particle Soil erodibility governed by clay content, particle size distribution, compaction , permeability, shear size distribution, compaction , permeability, shear strength parameters etc of the soil strength parameters etc of the soil

OBJECTIVES OF EROSION OBJECTIVES OF EROSION CONTROLCONTROL

To prevent damage to land adjacent to To prevent damage to land adjacent to the road structurethe road structure

To reduce the soil loss from the land To reduce the soil loss from the land width of road, which silts up drainage width of road, which silts up drainage channel and pollute riverschannel and pollute rivers

To contribute to the improvement of the To contribute to the improvement of the aesthetics of the landscapeaesthetics of the landscape

To protect and preserve the earth work of To protect and preserve the earth work of fill or cut slope, ditches and drainage fill or cut slope, ditches and drainage structurestructure

EROSION CONTROL SYSTEMEROSION CONTROL SYSTEM

TRADITION/ CONVENTIONAL TRADITION/ CONVENTIONAL METHODSMETHODS

Agronomic methodAgronomic methodNon-agronomic methodNon-agronomic methodNEW TECHNIQUES –ENGINEER NEW TECHNIQUES –ENGINEER INOVATIONINOVATION

Reinforced vegetationReinforced vegetationCoir geotextilesCoir geotextiles

AGRONOMIC METHODAGRONOMIC METHOD

Simple vegetative Simple vegetative trufingtrufing

Mulching of slopeMulching of slope

NON AGRONOMIC METHODNON AGRONOMIC METHOD

Proper road side drainage Proper road side drainage systemsystem

Soil cement stabilizationSoil cement stabilization

Provision of apronsProvision of aprons

REINFORCED VEGETATIONREINFORCED VEGETATIONReinforced vegetation by using geo-textiles Reinforced vegetation by using geo-textiles & other materials improving slop stability& other materials improving slop stability

Synthetics jute & coir used as geo-textilesSynthetics jute & coir used as geo-textiles

Geo-textiles are used for engineering Geo-textiles are used for engineering applications due to their long lifeapplications due to their long life

Disadvantage is that it causes air and water Disadvantage is that it causes air and water pollution while their non biodegradibility is pollution while their non biodegradibility is responsible for increasing soil pollutionresponsible for increasing soil pollution

COIR GEOTEXTILESCOIR GEOTEXTILESMade from coconut fiber extracted Made from coconut fiber extracted from the husk of the coconut fruitfrom the husk of the coconut fruit

It is a biodegradable organic fibre It is a biodegradable organic fibre material containing cellulose and material containing cellulose and ligninlignin

It gives max protection to the soilIt gives max protection to the soil

SOME NEW TRENDSSOME NEW TRENDS

SILT FENCESILT FENCE

CURLEX QUICK GRASSCURLEX QUICK GRASS

STEEL GROUND STAPLESSTEEL GROUND STAPLES

DE WITT PROSPUN DE WITT PROSPUN LANDSCAPE FABRICLANDSCAPE FABRIC

POLYPROPYLENE SAND BAGSPOLYPROPYLENE SAND BAGS

SILT FENCESILT FENCEDurableDurable

Light weightLight weight

Easy to useEasy to use

CULEX QUICK GRASSCULEX QUICK GRASS

STEEL GROUND STEEL GROUND STAPLESSTAPLES

Use to anchor your landscape fabricsUse to anchor your landscape fabrics

Each measures 6”L X 1” WEach measures 6”L X 1” W

DeWitt pros pun DeWitt pros pun Landscape FabricLandscape Fabric

Capability to Capability to stop weed stop weed growthgrowth

Environmentally Environmentally safesafe

Easy to useEasy to use

POLYPROPYLENE SAND POLYPROPYLENE SAND BAGSBAGS

White poly-stringWhite poly-stringtie bags are tie bags are made of wovenmade of wovenPolypropylenePolypropyleneString is String is attached toattached tothe bag.the bag.Each bagEach bagMeasuresMeasures14” W X 26” L14” W X 26” L

CONCLUSIONCONCLUSION In all new construction erosion levels In all new construction erosion levels

should be assessed in advance and should be assessed in advance and appropriate protection measures are appropriate protection measures are incorpoated in design.incorpoated in design.

In case of existing structures facing In case of existing structures facing erosion problems, both short term and erosion problems, both short term and long term measures should be considered long term measures should be considered to ensure stability. For overall economy to ensure stability. For overall economy use of locally available materials should be use of locally available materials should be the first choice. In extreme climatic the first choice. In extreme climatic conditions polymeric grids with root conditions polymeric grids with root reinforcing mechanism may be used even reinforcing mechanism may be used even though they are costlythough they are costly

REFERENCEREFERENCEAzeem A and Ali A (1992) Erosion causes Azeem A and Ali A (1992) Erosion causes and control techniques for slopes of banks and control techniques for slopes of banks and cuttings, proceeding Indian and cuttings, proceeding Indian geotecnical conference 1992 ,pp;457-462geotecnical conference 1992 ,pp;457-462

Indian highways vol 32 no:6 jane 2004Indian highways vol 32 no:6 jane 2004

Coir –organic fibre geotextiles for soil Coir –organic fibre geotextiles for soil erosion control –by coir board of Indiaerosion control –by coir board of India

THANKYOUTHANKYOU