Presentation on theme: "Dr. S. K. Chakrabarti INDIAN JUTE INDUSTRIES’ RESEARCH ASSOCIATION"— Presentation transcript:
1 Development of Durable Jute Geotextile for Erosion control of River bank Dr. S. K. ChakrabartiINDIAN JUTE INDUSTRIES’ RESEARCH ASSOCIATION17,Taratala Road, Kolkata
2 Brief BackgroundJute Geotextile (JGT) for its typical functional characteristics and eco-concordance has emerged out as a potential natural Geotextile for many civil engineering applicationsFor commercial exploitation of Jute Geotextile in addressing various geotechnical issues, there is a need to improve its end use specific functional propertiesRiver bank erosion being a recurrent problem in our country demands appropriate measures for its prevention wherein Jute Geotextile can be used with minimum adverse impactExisting practices of use copper and bitumen based compounds for enhancing life seems to be inadequate both technically and environmentallyFor wider acceptance of JGT in erosion control of river bank comprehensive durability of woven JGT under combined soil and water ambience has to be ensured by an ALTERNATE ROUTE.
3 Specification of woven Jute Geotextile Weight gsmWidth : metreEnds x Picks : 85x32/dmTensile strength (kN/m), MD x CD: 20 x 20AOS (micron) O95 : 150 – 400µ(Designed and developed by IJIRA- NJB)
4 Development of durable woven Jute Geotextile Organic Biocide: Isothiazolinone derivativeWater Repellent Compound: Fluorocarbon derivativeWet pick up : 80-90%Drying : 100ºCCuring : ºCPad –Dry –Cure MethodFabricPadding MangleTrough (Bath)Drying zoneCuring zone
5 Water Repellency of Specially Treated woven Jute Geotextile Water repellency of specially treated Jute Geotextile has been measured by Spray Test Method : As per IS , R.A in 2003 ,Cone Test: IS 7941: 1976, R.A in 2004, Bundesmann Test: ISO 9865: 1991Spray test methodUntreated JGTSpecially Treated JGTDurable JGT : 90% water repellent
6 Durability of woven Jute Geotextile under soil Sr. No.Woven Jute Geotextile% Retention in Strength( Under enriched soil after 21 days)1.Untreated JGT17.02.Specially Treated JGT88.0Soil Burial Test : As per IS: 1623, 1992
7 Characteristics of specially treated durable woven Jute Geotextile Sl. No.Test ParametersUntreated JGT Fabric(Control)Specially treated JGT Fabric (Experimental)ASTM /IS Standard1Weight (g/m2) at 20% MR631.7638.4D 5261 – 19962Ends x Picks /dm86.0 X 31.485 X 32IS: 1963 – 19813Tensile strength (kN/m) / Elongation at break (%)MDCD24.39 ( 7.08 )20.59 ( 8.04 )22.25 ( 7.14 )19.74 ( 8.16 )D 4595 – 944Permittivity at 50 mm constant water head per sec0.500.43D 4491 – 99a5Apparent Opening Size(μm) (O95)251234D 4751 – 99a6Rod Puncture Resistance(N)386.3373.8D 4833 – 20007Water Repellency (%)0.090.0IS:8% Retention in Strength (Under enriched soil after 21 days)17.088.0IS: 1623, 1992
8 Durability of specially treated JGT in Water Ambience Durability of both untreated and specially treated JGT in water ambience have been examined in the laboratory by putting the JGT fabrics on static water for different periods (up to 150 days) and finally their loss in tensile strength have been measured.Experiment on durability of treated JGT in Water Ambience
9 Loss in Strength of Durable Woven Jute Geotextile under Water Ambience WarpWeft
10 Durability test of JGT in combined Soil-Water Ambience at IJIRA Durability of Specially Treated woven JGT in Combined Water and Soil AmbienceBoth untreated and treated JGTs were put in simulated experimental river bank conditions and finally % loss in tensile strength of both untreated (control) and specially treated JGT under combined soil and water ambience were measured up to 150 days.Durability test of JGT in combined Soil-Water Ambience at IJIRA
11 Loss in Strength of Durable Woven Jute Geotextile under combined Soil-Water AmbienceWarpWeft
12 Microbial Analysis: As per Agar plate technique (AATCC 100, AATCC 30) Microbial profile of soil & water used in durability test of treated JGT(Microbial Count)(CFU/gm)SoilWaterBacteria2.0x 1072.7 x 102Fungi3.2 x104NegligibleMicrobial Analysis: As per Agar plate technique (AATCC 100, AATCC 30)Textural class of Soil used : Silt loam as tested by NBSS
14 Life Prediction of Specially treated woven Jute GeotextileLIFE PREDICTION of specially treated woven Jute Geotextile (627 gsm ) had been carried out at IJIRA both under soil ambience and soil-water ambience and compared with untreated grey Jute Geotextile fabric. At different interval, loss in tensile strength was monitored and finally a statistical life prediction model as represented in has been suggested.
15 Statistical Life Prediction of specially treated woven Jute Geotextile
16 Statistical Life Prediction of specially treated woven Jute Geotextile
17 ( Bhagirathi, Shantipur, Nadia, West Bengal ) Field Trial of Durable Woven JGT has been carried out at the left bank of the river( Bhagirathi, Shantipur, Nadia, West Bengal )In association with:1. National Jute Board (CFC-IJSG-21 Project)2. Department of Irrigation and Water ways, NadiaDivision Govt. of West BengalSite of trialPerformance Assessment of JGTBulk production of durable JGT
18 Field Trial on Specially Treated durable Woven Jute Geotextile
19 Salient features of Durable Woven JGT Identified chemical additives used to improve durability of woven JGT are aqueous based and readily availableThe effective add-on of the chemicals is low (0.5 %, w/w, approx.) and the weight gain of JGT fabric is negligibleThe loss of strength of the JGT fabric after treatment is within normal range (around 5%)Fabric characteristics of woven JGT are not affected much due to special treatmentSpecially treated woven JGT is rot-resistant & water repellentImproved functional properties is likely to increase the effectiveness of using such durable JGT in river bank protectionContd…
20 Salient features of Durable Woven JGT The treated JGT does not increase much the BOD and COD of water indicating no negative environmental impactFormulation developed for special treatment of JGT is user friendlyPredicted life of durable JGT is about two years in combined water-soil ambienceMay be considered as a cost effective alternative of copper and bitumen treatment in woven JGTFor large scale production of specially treated woven JGT, current cost of chemical is Rs /- per sq.mt excluding its processing cost
21 ConclusionDurable woven Jute Geotextile with improved anti-microbial and water repellent properties and useful life under combined soil-water ambience may be used for erosion control of river bank.Short and long term performance evaluation of durable woven JGT in erosion control of river bank are in progress.
22 acknowledgementNational Jute Board, Ministry of Textiles, Govt. of India forsponsoring the Project activityCFC-IJSG-21 PROJECT for providing support in field levelperformance evaluation of durable JGT in erosion control of riverbank