1. Department of Civil Engineering
LOAD SETTLEMENT BEHAVIOUR OF JUTE GEOTEXTILE REINFORCED SUBGRADE OF RURAL ROAD USING ABAQUS
Sudip K. Roy Ambarish Ghosh Ashis Kumar Bera Sandip Chakraborty
Department of Civil Engineering
Bengal Engineering and Science University, Shibpur Howrah – June, 2013

2. Why Numerical Analysis?

3. SELECTION OF NUMERICAL TOOL

4. LITERATURE REVIEW Researchers Research Area/ Findings
S. Pirabarooban, M. Zaman, R. A. Tarefder. (2003)
FEM results show that the ABAQUS-based model can adequately account for cyclic loading and other factors and, as such, it can be used effectively to evaluate the rutting potential of in-service pavement.
K. Nesnas, M. Nunn. (2004)
A response model (3D) is generated in ABAQUS to predict top down cracking
R. Zafar, W. Nassar and A. Elbella. (2005)
In this study the finite element software ABAQUS is used to study stress redistribution due to the presence of earth pressure cell (vertical stress-measuring instrument) in the pavement layers
W.G. Buttlar, G. H. Paulino, and S. H.Song. (2006)
Numerical examples and an implementation using the user material subroutine UMAT of the finite element software ABAQUS are also provided to illustrate the benefits of using graded elements in pavement analysis.

5. LITERATURE REVIEW Researchers Research Area/ Findings
Tabakovic, Amir; McNally, Ciaran; Sorelli, L. G.; Gibney,
Amanda; Gilchrist, M. D. (2006)
A damage mechanics model has been developed in order to compare the behaviour of RAP (Recycled Asphalt Pavement), The damage model was implemented within the ABAQUS finite element code using a UMAT subroutine
Grace G. Abou-Jaoude, Ziad G. Ghauch
A 3D Finite Element model of the pavement involving a linear viscoelastic constitutive model for HMA materials and non-uniform tire contact stresses is developed using ABAQUS 6.11 to investigate the effectiveness of several design strategies involved in long-life, perpetual pavement design
A.M.Khaki, E. Azadravesh. (2010)
A 3D FE model is generated by ABAQUS for evaluating the effects of joint opening on load transfer efficiency in concrete pavements
Rahman M.T , Mahmud K, Ahsan S. (2011)
In this study, a 3D finite element model of flexible pavement is developed using ABAQUS for better prediction of mechanical behaviour and pavement performance subjected to various traffic factors.

6. LITERATURE REVIEW Researchers Research Area/Findings
B. Sukumaran, V. Kyatham, A. Shah, D.Sheth. (2004)
The stress-strain response of the various soils is simulated using an elasto-plastic model and von Mises strength criteria available in finite element code ABAQUS. The empirical relationship between CBR and resilient modulus is investigated based on the results obtained from the three dimensional finite element analyses.
Gholam Ali Shafabakhsh, Abbas Akbari. (2013)
3D modelling with help of finite element computer code ABAQUS has been used to determine the role of different parameters of passenger, commercial and military airplane’s main gear s which cause the major failures to the rigid runway pavements.
Gholam Ali Shafabakhsh, Mana Motamedi, Afshin Family. (2013)
This research, at first, tends to investigate influence of changing asphalt pavement thickness in vertical strain using finite element software (ABAQUS) and finally, the results related to the finite element, were compared with experimental data.

7. ABAQUS A Finite element Software
Robustness in numerical solution strategy for soil nonlinearity,
Capable of solving most geotechnical problems,
Involving two- and three-dimensional configurations,
Soil and structural elements,
Wide range of material property can be used
Total and effective stress analysis,
Consolidation analysis,
Seepage analysis,
Static and dynamic analysis, etc.

8. ABAQUS
Huang et al. (2006) carried out finite element analysis to study the consolidation behaviour of an embankment on soft ground.
Hadi and Bodhinayake (2003) carried out finite element analysis of road emabankment in ABAQUS.
Kuo and Chou (2004) developed and analyzed a three dimensional model for flexible pavement using ABAQUS software

9. Jute Geotextile Application
Bera et al. ( 2009 ) carried out series of unconfined compression strength tests of fly ash reinforced with jute geotextile.
Chattopadhyay and Chakraborty ( 2009 ) studied the application of JGT as facilitator in drainage.
Sahu et al. ( 2004 ) carried out model footing test to determine the behaviour of JGT reinforced soil bed and to asses aging effect of soil along with degradation of JGT with time

10. Fig.1 Unreinforced Road Section
Rajar hat Test Track
A trial stretch road section:
Data Given:
CBR=3% (assumed)
ESAL=60000 to
Unreinforced Road Section
As per IRC: SP: , Subgrade Strength as per CBR=3%; it is Poor.
Premix Carpet = 20 mm
WBM (Grade-II) = 75 mm
WBM (Grade-III) = 100 mm
GSB(Grade-II) =150 mm
Fig.1 Unreinforced Road Section

11. Rajar hat Test Track
Fig.2 Unreinforced Road Section ( Reduced GSB )

12. Rajar hat Test Track
Fig 3.Reinforced Road Section with JGT (20kN/m)

13. Rajar hat Test Track
Fig 4.Reinforced Road Section JGT (25kN/m)

14. Rajar hat Test Track
Fig 5.Reinforced Road Section with Geosynthetics

15. Unreinforced road section
Problem Description
Unreinforced road section
Unreinforced Road Section ( Reduced GSB )
Reinforced Road Section with JGT (20kN/m)

16. Fig.6 Unreinforced road section (UR GSB 100 )
Geometry of the Model
Fig.6 Unreinforced road section (UR GSB 100 )

17. Fig.7Unreinforced road section (UR GSB 175 )
Geometry of the Model
Fig.7Unreinforced road section (UR GSB 175 )

18. Fig.8 JGT ( 20kN/M ) Reinforced road section (GSB 100 )
Geometry of the Model
Fig.8 JGT ( 20kN/M ) Reinforced road section (GSB 100 )

19. Material property Material Model used Density (kN/m3)
Elastic Modulus (MPa)
Poisson’s ratio
Friction angle (Degree)
Dilation angle
Cohesion
(kPa)
WBM
Linear Elastic
15.2 19
0.4 NA
GSB
14.5 20
Sand
15.5 15
0.3
JGT 80
Subgrade
Mohr-Coulomb model
13.95 10 2 30
Existing soil layer
Mohr- Coulomb model
14.0 12

20. LOAD Static Load & Boundary Condition
Fig. 9 Load and Boundary condition applied to the model (Reinforced section, JGT100)

21. Cyclic load and Time Stepping

22. INTERACTION

23. Meshing Criteria
( a ) UR GSB 100
( b )REINFORCED
Fig.10 Mesh model

24. Results and Discussions
Deformed Shape
Fig.11 Deformed shape for UR GSB 100

25. Results and Discussions
Deformed Shape
Fig.12Deformed shape for UR GSB 175

26. Results and Discussions
Deformed Shape
Fig.13 Deformed shape for JGT Reinforced Section

27. Results and Discussions
Deformed Shape
JGT
Fig.14 Deformed shape for JGT Reinforced Section

28. Results and Discussions
Deformed Shape
Fig.15 Deformed and Undeformed shape for JGT Reinforced Section

29. Results and Discussions
Fig.16 Tensile stress ( ) & Compressive stress ( )

30. Results and Discussions
Fig.17 Typical Load settlement plot at subgrade unreinforced ( UR GSB 100 ) road section ( by using cyclic loading)

31. Results and Discussions
Fig.18 Typical Load settlement plot at subgrade Reinforced road section ( Cyclic loading )

32. Results and Discussions
Effect of JGT on rut depth of road section
Fig.19Load (Static) vs. Rut depth (mm)

33. Results and Discussions
Effect of JGT on rut depth of road section
Fig.20 Rut depth (mm) for the three models ( Subgrade top )

34. Results and Discussions
Effect of JGT on rut depth of road section
Fig.21 Comparison between rut depth for unreinforced ( URGSB 100 ) and reinforced model after 8 hours vehicle movement at an interval of 45 second

35. Results and discussions
Effect of JGT on stresses developed of Subgrade top

36. Conclusions
With the introduction of JGT reinforcement in between subgrade and granular base layer the values of rut depth decreases significantly.
Cyclic loading developed larger rut depth compared to static loading irrespective of types of road section.
Stress developed on the subgrade top in case of JGT reinforced road section is much lesser than road section without reinforcement.
ABAQUS software can effectively analyse the any types of road sections ( Reinforced & Unreinforced ). By using this software researcher may observe any types of load ( compressive/ tensile ), directions, deformations at any point.

37. References
Bera, A.K., Chandra, S.N., and Ghosh, A. ( 2009 ) “ Unconfined compressive strength of fly ash reinforced with jute geotextiles”, Geotextiles and Geomembranes, 27 ( 5 ), pp
Bhasi.A. Rajagopal, K.(2010) “Finite Element Analysis of Geosynthetic reinforced pile supported embankments.” SIMULIA Customer Conference.
Chattopadhyay, B.C., and Chakraborty, S. ( 2009 ) “ Application of jute geotextiles as facilitator in drainage”, Geotextiles and Geomembranes, 27 ( 2 ), pp
Hadi,N.S. and Mukammad. Bodhinayake, B.C. (2003) “Non-linear finite element analysis of flexible pavements” Elsevier, Advances in Engineering Software , 34, pp.657–662.
Helwany, S. Dyer, J. and Leidy, J. (1998) “Finite element analysis of flexible pavement.” , Journal of transportation engineering, September/October, pp
Helwany,S.(2007) “Applied soil mechanics with Abaqus application”, John Wiley & Sons.
Kuo, C.M, Chou, F.J. (2004). “Development of 3-D Finite Element model for Flexible Pavements” Journal of the Chinese Institute of Engineers, 27, ( 5 ),
Sahu, R.B., Hazra, A.K.and Som, N. ( 2004 ) “ Behaviour of geojute reinforced soil bed under repetitive loading- a model study” BCC iInternational Conference on Geosynthetics and Geoenvironment Engineering, Bombay

38. Thank You