CONTENTS 1 . Introduction . 1.1 Definition. 2 . Functions of geotextiles. 3 . Classification 4 . FIBRES USED IN GEOTEXTILE 5 . Production process of geotextiles 6 . FORMS OF GEOTEXTILE Application of geotextiles References
FUNCTIONS AND APPLICATION OF GEOTEXTILEApplication Geotextile function Reinforcement separation Filtration Drainage protectionRoads P T T S TRail roads S P S P TSurface T S P T TdrainageSteep sloper P T T S SLand fills S P P S PWalls P T T T TSoil P T S S TreinforcementCoastal P T P S Tprotection
PROPERTIES OF NATURAL FIBER TYPE OF FIBERProperty Flax Jute Hemp Sisal Abaca CoirFiber 200-1400 1500-3600 1000-3000 600-1000 1000-2000 150-350length(mm)Fiber 0.04-0.62 0.03-0.14 0.16 0.1-0.46 0.01-0.28 0.1-0.45diameter(mm)Fiber linear 2-20 14-20 3-22 10-450 40-440 -density(d/tex)Fiber 0.54-0.57 0.41-0.52 0.47-0.60 0.36-0.44 0.35-0.67 0.18tenacity(N/tex)
SYNTHETIC FIBERSSYNTHETIC FIBERS:- polypropylene Polyester polyamide(nylon 6,nylon 66) polyethylene.Polypropylene:-Advantage :- low density results low cost per unit volume acceptable tensile property high fatigue resistance.Disadvantage:- Sensitive to ultra violet radiation Sensitive to high temperature
Polyester :- Superior Creep Resistance C Have High Tenacity Values Suitable For High Stress Application S Suitable For Elevated Temperature Applications Near About180 - 200 C High Abrasion Resistance High Resistance To Ultra Violet Rays. High Modulus Example: Roofing, Separation And Filtration ApplicationsPolyamides:- High Strength And Creep Properties . Fabric structures and finishing treatments influence their properties
FORMS OF GEOTEXTILE Geomembrane Geogrids Geonets Geocomposite Geomat Geocell Biomet and Bionet
GEOMEMBRANES:-These are used primarily for liningsand covers of liquid or solid storage facilities .These are essentiallyimpermeable material in the form of manufactured sheet which maybe synthetic. Thus the primary function is always as a liquid or gasbarrier .The range of application is very high. These are act as abarrier for flow of water or any hazardous liquid. The simplestexample is canal lining Non-Woven Compound Geo membrane
GEOGRIDS These can be in the form of manufactured sheet, consisting of a regular network of integrally connected elements, which may be linked by extrusion , bonding. Have high tensile strength and dimensional property at very low elongation. Coated polyester geogrids widely used in soil stabilization and Geotechnical reinforcement of retaining walls and embankment applications. Biaxial geogrids are used as separator in between sub grade and aggregate Woven /knitted polyester coated geogrid used for wall retaining applications
fiberglass geo grid compositewith non woven geo textile
ACCORDING TO PHYSICAL STRUCTURE GEOGRIDS CAN BE CLASSIFIED INTO FOLLOWING CATEGORIES . Unidirectional Geogrid:-possessing high tensile strength in one direction (that is longitudinal and transversal) than in the other direction. Bidirectional Geogrid:- possessing similar tensile strength in both direction that is longitudinal and transversal. Extruded Geogrid:-produced by stretching uniaxially or biaxially an extruded integral structure . Bonded Geogrid:- produce by bonding stretching right angles , two or more sets of strands filaments and yarns. Woven Geogrid:- produce by interlacing at right angle, two or more sets of strands filaments and yarns.
GEONETS These are usually formed by continues extrusion of parallel sets of polymeric ribs at acute angels to each other. These net like configuration are mostly useful in drainage application . These are look like geogrid but have substantially lower strength These are used for drainage applications because these are provide space between two non woven textiles to minimize clogging and any possible leakage from either of the membranes as a geocomposites.Three Dimensional Geo net
GEOCOMPOSITES When geogrid/Geomembranes are combined with woven or non woven Geotextile for specific application like drainage, erosion control, bank embankment, etc. then they are designed as GeoComposites. A typical example is bentonite geocomposite. It consists bentonite filled pores when this geotextile come in contact with water the bentonite causes the pores to swell thereby forming water tight sheets. Glass fibers are knitted on to the non woven geotextiles to enable better use in highway applications. Geo composite is made by laminating a nonwoven geo textile
GEOMATIt is a polymeric structure in the form of manufactured sheetThese are used for erosion control and soil reinforcement like inrunning canals
GEOCELL It is a polymeric cellular structure consisting of a regular open network of connected stripes linked by extrusion , adhesion or by other methods. These are used as embankment geo textile which have high tensile strength to prevent bank from the cracks .The rigidity of these textile ensure the even distribution of force exhibited by water. The Geocell is soil infill. protection of outer cell by topsoil.
Biomat and Bionet These are permeable , natural and therefore biodegradable polymeric material in the form of the manufactured sheet. Biomat consists of fiber such as jute , coir, sisal, straw, are kept together by one or two layers of synthetic or natural meshes and bionet consist of a regular network of knotted or interlaced yarns whose openings are lager than the constituents. Jute are used for moisture holding capacity of soil these are degrade into the soil and reduce the velocity of flow of water and hold the fertile soil at place.
APPLICATION OF GEOTEXTILE Separation Filtration Drainage River bank protection Coastal protection Reservoirs and lakes Concrete mattresses Reclaimed lands Embankment Railway/Roadway Landfills Soil erosion controls
RETAINING WALL These withstand the effect of earthquakes better than conventional rigid concrete walls. Reinforcing material should have high tensile strength, stiffness, pullout and sliding resistance, durability.
ROCK FALL PROTECTION Highway and rail roads near rocks ,slopes are needed the rock fall protection geo grid textile are used for that purpose
REFERENCES Textile progress , September 2010 , volume 42 , no.3 , page 181-189 Asian Textile Journal , September 2006 , volume 15 , no.7-9 , page 89-94 Asian Textile Journal , February 2006 , volume 15 , no.3-3 , page 39 Asian Textile Journal , February 2004 , volume 13 , no.1-4 , page 68-71 Asian Textile Journal , September 2005 , page 88-93 Indian journal of fiber and textile ressearch,1997 December Non Woven And Geo textile, January 1988