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Jute Geotextile – Potential and Application in Road Works. Sudhir Mathur Chief Scientist & Advisor (Planning and Policy Issues) Central Road Research Institute New Delhi. Geotextile Usage.
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Jute Geotextile – Potential and Application in Road Works Sudhir Mathur Chief Scientist & Advisor (Planning and Policy Issues) Central Road Research Institute New Delhi
Geotextile Usage • Billions of square m of geotextiles is estimated to have been used world wide last year – China using about 50 per cent of this quantity • About 10 million square m of geosynthetics used in India last year, worth several million US $ • Huge potential for usage of geosynthetics in on-going road development projects • Jute/Natural fabrics also has a large potential for future road projects- but not been marketed as vigorously as synthetic
Jute Geotextile Usage – Potential Areas • Largest potential areas are hill roads and embankment slope protection from erosion control • Other areas are separation, filtration, sub-surface drainage and reinforcement to some extent.
Publications by IRC • State of Art Report: Use of Jute Geotextiles in Road Construction and Prevention of Soil Erosion/Landslide. Special Report 21-2012 • MoRTH ,2013- Standard Specifications for Road and Bridge works › Section 700; Clause 707 deals with NATURAL GEOTEXTILE The work covers the use of natural geotextiles for control of erosion of slopes including supplying and laying the mat spreading soil and seeding to promote the growth of vegetation, as per design, drawing and these specifications. ›Natural Geotextile shall be used to control surface erosion of top cover soil on cut or fill slopes and to facilitate vegetation to grow. Strength Requirements: The natural fibre geotextiles made of Jute shall meet the minimum requirement as stated in IS 14715- Woven Jute Geotextiles – Specification.
Use of Jute Geotextilesfor Improving Performance of PMGSY Roads(Pilot Project) • To study the use of jute geotextile in the road pavement (Benefit of JGT of varying strength as an agent for improvement in load bearing capacity of the subgrade, specifically the subgrade CBR and overall improvement in pavement performance) • Role of open weave JGT as bio-engineering protective measure by facilitating growth of vegetation on the embankment slopes and earthen shoulders • DPR for 10 Pilot project under varying soil/ climatic conditions was prepared jointly by CRRI & JMDC for 5 States namely West Bengal, Assam, Orissa, Madhya Pradesh and Chatisgarh • However, due to certain technical and administrative problem only 5 roads could be completed.
Use of Jute Geotextiles (JGT) for Improving Performance of Rural Roads PMC PMC W.B.M To study the use of jute geotextile in the road pavement as a drainage layer, Bioengineering measure for shoulders and earthen slopes, Improving the pavement performance and Reducing the pavement crust thickness • Pavement sections as per IRC Practice, Thinner pavement sections without JGT and Test sections incorporating different varieties of JGT • Pilot project taken up in 5 PMGSY roads across five states under varying soil/ climatic conditions JGT (Open Weave) Control Section II JGT Test Sections PMC PMC PMC W.B.M W.B.M W.B.M W.B.M Gravel Gravel Gravel GSB GSB GSB GSB Sand Bed Subgrade JGT + Sand Sand Bed JGT + Sand Subgrade Control Section I
TYPICAL ROAD SECTIONS ADOPTED IN PMGSY PROJECT Pavement cross section with IRC-SP-20 (Conventional section I )
TYPICAL ROAD SECTIONS ADOPTED IN PMGSY WITH REDUCED CRUST Pavement cross section with reduced thickness (Conventional section II)
ROAD SECTIONS IN ASSAM WITH REDUCED CRUST SECTIONS Jute geotextile as a separator
ROAD SECTIONS FROM JARBARI TO BARNIGAON AT ASSAM Jute geotextile as a separator and turfing
Control Section Without JGT – Gehlawan to PMGSY Road (M.P – 2009)
Distress in Control Section Rampur Satra to Dumdumia Road (Assam – 2009)
Pavement Distress in JGT Section Rampur Satra to Dumdumia Road (Assam – 2009)
Measurement of Deflection through BBD Studies at another site
CONCLUSIONS • The performance of JGT incorporated sections with reduced pavement crust viz- a- viz control section (with conventional pavement thickness) have exhibited similar performance in terms of distress and characteristics deflection (a measure of structural strength of pavement). • 2) No conclusive decision based on performance data can be made regarding the improvement in pavement performance with geotextile of higher strength. • 3) The characteristics deflections in some of the test sections with jute geotextile remain more or less unchanged over a period of time. It indicate that test sections with jute geotextile structurally remain stable despite lesser thickness.
4) The pilot project studies were also aimed to find out improvement in subgrade, which can be achieved by using jute geotextile. It was expected that the inclusion of jute geotextile would absorb/ drain the excess moisture in the subgrade and would result in the improvement of soil subgrade strength in terms of CBR. Several DCP tests were carried out at different locations of the test sections. However, with two cycles of performance observation data, non conclusive decision could be made to reveal any appreciable improvement in in-situ CBR values.
5) Open weave JGT, which was used is a bio-engineering measure to pavement erosion has performed very satisfactorily. It clearly suggests that jute geotextile is very effective to prevent erosion and protecting side slopes. 6) Since the traffic generated on these selected low volume roads is not very significant, it is difficult to exactly quantify the benefits of incorporating jute geotextile based on two sets of performance observations. 7) It is therefore suggested that to arrive at definite conclusions about performance of JGT incorporated pavement sections, more roads be constructed and performance observations be taken at least for a period of five years.
