Numerical Study of the Effect of Reinforcing Subgrade on Behavior of Reinforced Test Sections by FEM

Document Type : Research Paper

Authors

1 Associate Professor, Faculty of Civil Engineering, Semnan University, Semnan, I. R. Iran.

2 MSc. Student, Faculty of Civil Engineering, Semnan University, Semnan, I. R. Iran.

Abstract

One of the appropriate methods to improve the roadway, built on the weak subgrade, is using geosynthetic reinforcement that is highly regarded. Few field and laboratory tests have been planned and conducted under the real traffic loading to investigate the behavior of reinforced subgrade and achieve suitable design methodology. However, due to such limitations as high costs of laboratory or field tests, their implementation is limited. Numerical simulation methods can help to study the performance of such reinforced roads and evaluate the effect of important parameters. In this research, three-dimensional finite element method (FEM) was used to investigate the behavior of the geosynthetic reinforced roads under traffic loads, and the results were validated with field data. Results of the numerical modeling and field studies showed that the numerical model can predict the behavior of a geogrid-reinforced system and there was a good agreement between the results of field studies and modeling responses. Results of the  numerical study also showed that the settlement of reinforced road is strongly influenced by the mechanical properties of reinforcement, including the stifness of the geogrid. Reduction of geogrid stifness by 50%, increased the surface settlement by about 61%. Also, effect of the stiffness of subgrade and base layer in reinforced test section on the surface settlement was 50% less than the unreinforced test section. Results showed TBR increase by 26.11 times due to the reinforcement of the test section with a strong reinforcing agent. 

Keywords


AASHTO. 1993. “Guide for Design of Pavement Structures”. American  Association  of  State  Highway  and Transportation Officials, Washington, D. C.
Abdessemed, M., Kenai, S. and Bali, A. 2015. “Experimental and numerical analysis of the behavior of an airport pavement reinforced by geogrids”. Constr. Build. Mater., 94: 547–554.
Abebe, M. S. and Qiu, H. S. 2016. “Numerical modeling of geotextile reinforcement of soft subgrade ballasted railway under high speed train”. EJGE, 21: 4327-4343.
Al-Azzawi, A. A. 2012. “Finite element analysis of flexible pavements strengthened with geogrid”. ARPN J. Eng. Appl. Sci., 7(10): 1295-1299.
Al-Qadi, I. L., Dessouky, S. H., Kwon, J. and Tutumluer, E. 2008. “Geogrid in Flexible Pavements: Validated Mechanism”. Transportation Research Record 2045, Transportation Research Board, National Research Council, Washington D. C., pp. 102-109.
Biabani, M. M., Indraratna, B. and Ngo, N. T. 2016. “Modelling of geocell-reinforced subballast subjected to cyclic loading”. Geotextiles Geomembranes, 44: 489-503.
Cho, Y., McCullough, B. F. and Weissmann, J. 2000. Consideration on finite-element method application in pavement structural analysis. Transportation Research Record 1539, TRB National Research Council, Washington, D. C., pp. 96-101.
Cuelho, E. and Perkins, S. 2009. “Field Investigation of Geosynthetics Used for Subgrade Stabilization”. FHWA/MT-09-003/8193, Western Transportation Institute, Montana State University, Bozeman, pp. 5-80.
Duncan, J. M., Monismith, C. L. and Wilson, E. L. 1968. “Finite Element Analysis of Pavement”. Highway Research Record, No. 228, TRB, Washington, D. C.
Gu, J. 2011. “Computational modeling of geogrid reinforced soil foundation and geogrid reinforced base in flexible pavement”. PhD Dissertation, Louisiana State University.
Hadi, M. N. S. and Bodhinayake, B. C. 2003. “Non-linear finite element analysis of flexible pavements”. Adv. Eng. Software, 34: 657-662.
Han, J., Pokharel,  S., Yang,  X., Manandhar,  C., Leshchinsky,  D., Halahmi  I. and Parsons, R. 2011. “Performance of geocell-reinforced RAP bases over weak subgrade under full-scale moving wheel loads”. J. Mater. Civ. Eng., 23(11): 1525-1534.
Hilton, S. T. 2017. “Full-scale pavement testing of aggregate base material stabilized with triaxial geogrid”. MS Thesis, Brigham Young University.
Hua, J. 2000. “Finite element modeling and analysis of accelerated pavement testing devices and rutting phenomenon”. PhD Dissertation,Purdue University, West Lafayette, Indiana, USA.
Huang, H. 1995. “Analysis of accelerated pavement tests and finite element modeling of rutting phenomenon”. PhD Dissertation, Purdue University, West Lafayette, Indiana, USA.
Huang, W. C. 2014. “Improvement evaluation of subgrade layer under geogrid-reinforced aggregate layer by finite element method”. Int. J. Civ. Eng., 12(3): 204-215.
Huang, Y. 2004. “Pavement Analysis and Design”. 2nd Edition, Pearson Education, New Jersey.
Huekelom, W. and Klomp, A. J. G. 1962. “Dynamic Testing as a Means of Controlling Pavements During and After Construction”. Proceedings of the First International Conference on the Structural Design of Asphalt Pavements, Ann Arbor, Michigan,  pp. 667-685.
Hufenus, R., Rueegger, R., Banjac, R., Mayor, P., Springman, S. M. and Bronnimann, R. 2006. “Full-scale field tests on geosynthetic reinforced unpaved roads on soft subgrade”. Geotextiles Geomembranes, 24(1): 21-37.
Hussein, M. G. and Meguid, M. A. 2013. “Three-dimensional Finite Element Analysis of Soil-geogrid Interaction under Pull-out Loading Condition”. GeoMontreal 2013, the 66th Canadian Geotechnical Conference, Montreal, Quebec, Canada, Paper No. 260, pp. 452-458.
Hussein, M. G., Meguid, M. A. 2016. “A three-dimensional finite element approach for modeling biaxial geogrid with application to geogrid-reinforced soils”. Geotextiles Geomembranes, 44: 295-307.
Ibrahim, S. F., Sofia, G. G. and Kareem, A. I. 2012. “Experimental study on geogrid-reinforced subbase over soft subgrade soil under repeated loading”. J. Eng. Dev., 16(3): 218-240.
Ibrahim S. I., Ahmed, N. G. and Mohammed, D. E. 2016. “Effect of reinforcement on improve surface pavement for weak  subgrade conditions”. Int. J. Geomate, 11(23): 2188-2193.
Kim, M. 2007. “Three-dimensional finite element analysis of flexible pavaments considering nonlinear pavement foundation behavior”. PhD Dissertation, University of Illinois, Urbana, Champaign.
Leng, J. and Gabr, M. 2005. “Numerical analysis of stress-deformation response in reinforced unpaved road sections”. Geosynth. Int., 12: 111-119.

1-1-            Leonardi, G. and Palamara, R. 2017. “Finite Element Modelling of Flexible Pavement Reinforced with Geogrid”. Proceedings of the International Congress on Transport Infrastructure and Systems, Rome, Italy, pp. 477-484.

Maxwell, S.,W. H., Edil, T. B. and Benson, C. H. 2005. “Geosynthetics in Roadways and Pavements”. National Highway Institute, Report No. FHWA-NHI-07-092.
Moghadas Nejad, F. 2004. “Non linear finite element analysis of  reinforced and unreinforced pavements”. Int. J. Eng., Trans. A: Basics, 17: 214-226.
Nagy, A. C., Moldovan, D. V., Ciotlaus, M. and Muntean, L. E. 2017. “Evaluation of  experimental and numerical simulation of triaxial geogrid reinforcement on strength of road structures”. Proc. Eng., 181: 472-479.
Nair, A. M. and Latha, G. M. 2015. “Large diameter triaxial tests on geosynthetic-reinforced granular subbases”.J. Mater. Civ. Eng., 27(4): 1-8.
Perkins, S. S. 2002. “Evaluation of Geosynthetic Reinforced Flexible Pavement Systems Using Two Pavement Test Facilities”. Report No. FHWA/MT-02-008/20040, U.S. Department of Transportation, Federal Highway Administration, Washington, D.C.
Perkins, S. W., Christopher, B. R. and Cuelho, E. L. 2004. “Development of Design Methods for Geosynthetic Reinforced Flexible Pavements”. Report No. DTFH61- 01-X-00068, Federal Highway Administration, Washington, D. C.
Saghebfar, M. 2014. “Performance of geotextile-reinforced bases for paved roads”. PhD Dissertation, Kansas State University, Manhattan, Kansas.
Tang, X., Stoffels, S. M. and Palomino, A. M. 2016. “Mechanistic-empirical approach to characterizing permanent deformation of reinforced soft soil subgrade”. Geotextiles Geomembranes, 44: 429-441.
Tingle, J. and Webster, S. 2003. “Corps of Engineers design of geosynthetic-reinforced unpaved roads”. Transport. Res. Record, 1849: 193-201.
Uzarowski, L. 2006. “The development of asphalt mix creep parameters and finite element modeling of asphalt rutting”. PhD Dissertation, University of Waterloo, Waterloo, Ontario, Canada.
White, T. D., Haddock, J. E., Hand, A. J. T. and Fang, H. 2002. “Contributions of Pavement Structural Layers to Rutting of Hot Mix Asphalt Pavements”. Transportation Research Board, National Research Council, National Cooperative Highway Research Program, NCHRP Report 468, Washington, D.C.
Wu, H., Huang, B., Shu, X. and Zhao, S. 2015. “Evaluation of geogrid reinforcement effects on unbound granular pavement base courses using loaded wheel tester”. Geotextiles Geomembranes, 43(5): 462-469.
Yetimoglu, T., Wu, J. T. H. and Saglamer, A. 1994. “Bearing capacity of rectangular footings on geogrid-reinforced sand”. J. Geotech. Eng., 120(12): 2083-2099.
Zornberg, J. G. and Gupta, R. 2010. “Geosynthetics in Pavements: North American Contributions”.9th International Conference on Geosynthetics, Brazil, pp. 379-398.