Investigation of bridge abutment displacements constructed on piles and geogrid reinforced soil using the finite-element method

Authors

1 Department of Civil Engineering, University of Zanjan, Zanjan, Iran.

2 Department of Civil Engineering, Tabriz University, Tabriz, East Azarbaijan Province, Iran.

3 Road, Housing & Urban Development Research Center, Tehran, Iran.

Abstract

One of the major problems in highway and railway bridges is the settlement of the bridge abutments, which its reduction has always been set as the research target. Two methods which have been widely used for controlling the settlement are either reinforcing the abutment subsoil with geogrid orconstructing the abutments on piles. This paper describes the application of a two-dimensional finite element method (FEM) by using Plaxis2D V8.5 for comparing the performance of these two methods. The effect of the geogrid normal stiffness, length and depth of reinforcement on the horizontal and vertical displacement of abutment is also investigated. Data from an instrumented bridge abutment has been used for the model verification. The reduction of the bridge abutment,the vertical settlement and the horizontal displacement by pile and geogrid have been analysed and compared.It is found that constructing the abutment on piles has a better performance in reducing the vertical settlement of the bridge abutment. However, lower lateral displacement can be obtained by using a geogrid with a higher normal stiffness. It is also found that, while the vertical settlement is not affected by the geogrid stiffness, the horizontal displacement of the abutment decreases with increasing the stiffness.

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References:
1. Randolph, M.F. "Science and empiricism in pile foundation design", Geotechnique, 53(10), pp. 847-875 (2003).
2. Zhang, W., Qin, B., Wang, B., and Ye, J. "Reduction of earth pressure and displacement of abutment with reinforcement filling", Geotechnical Eng. for Disaster Mitigation and Rehabilitation, 20, pp. 815-820 (2008).
3. Detert, O. and Alexiew, D. "Physical and numerical analyses of geogrid-reinforced soil system for bridge abutments", From Research to Design in Europe. Practice Conf. Bratislava, Slovak Republic (2010).
4. Hara , T., Yu , Y., and Ugai, K. "Behavior of piled bridge abutments on soft ground: A design method proposal based on 2D elasto-plastic-consolidation coupled FEM", Comput. and Geotech., 31, pp. 339-355 (2004).
5. Lee, K.Z.Z. and Wu, J.T.H. "A synthesis of case histories on GRS bridge-supporting structures with flexible facing", J. Int. Geotex. and Geomembr, 20, pp. 181-204 (2004).
6. Skinner, G.D. and Rowe, R.K. "Design and behavior of a geosynthetic reinforced retaining wall and bridge abutment on a yielding foundation", Geotex. and Geomembr., 23, pp. 234-260 (2005).
7. Ellis, E.A. and Springman, S.M. "Modelling of soilstructure interaction for piles bridge abutment in plane strain FEM analyses", Computs. and Geotech., 28, pp. 79-98 (2001).
8. Wang, H.T., Chen, Z.P., and Xiao, L.J. "Plane strain finite element analysis of a piled bridge abutment on soft ground", 1st Conf. Comput. Meth. in Eng. and Science, Tsinghua University Press and Springer, pp. 600-607 (2006).
9. Fahel, S., Palmeria, E.M., and Ortigao, J.A.R "Behaviour of geogrid reinforced abutments on soft soil in the BR 101-SC highway, Brazil", Conf. on Advances in Transport. and Geoenviron. Sys. Using Geosynthetics, ASCE, pp. 257-270 (2000).
10. Zheng, Y. and Fox, P. "Numerical investigation of geosynthetic-reinforced soil bridge abutments under static loading", J. of Geotec. and Geoen. Eng., 40, pp. 1-13 (2016).