Experimental and Numerical Study of Micropiles to Reinforce High Railway Embankments

The construction of railway embankments on loose beds using reinforcing elements results in a modification of the embankments slope, which significantly reduces the amount of earthworks. In addition, reinforcement of both bed and embankment is essential to increase the load-bearing capacity and control the settlements. A solution for high railway-embankment stabilization and enhancing the operational axle load is the use of micropiles in the embankment toe to transmit the applied loads to the firm underlying layers and avoid the deep sliding of loose subgrade. This paper presents three experimental models of embankments of 10 m in height on a scale of 1/20 to set up a number of loading tests: one based on a non-reinforced embankment and two others based on reinforced embankments that are stabilized with two different arrangements of micropiles. During laboratory tests, the data, including the load-bearing capacity of embankments, displacements of embankment crest and bed surface, and axial strain of micropiles were measured using the instrumentation tools. In the next step, three numerical models were developed by using the PLAXIS-3D code based on the finite element method (FEM). Then, a comparison was made between the experimental and numerical data to verify the outputs of the numerical analyses. In the procedure of numerical analyses, elastoplastic behaviors of embankment material and bed were defined based on the Mohr-Coulomb failure criterion, and micropiles were considered as linear elastic elements. Finally, after accomplishing a series of sensitivity analyses on the geometric parameters of micropiles, their efficiency factor was classified in the process of arrangement optimization.

• Record URL:
  • https://doi.org/10.1061/(ASCE)GM.1943-5622.0000280
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/15323641
• Supplemental Notes:
  • Copyright © 2013 American Society of Civil Engineers
• Authors:
  • Esmaeili, Morteza
  • Nik, Morteza Gharouni
  • Khayyer, Farid
• Publication Date: 2013-12

Language

• English

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: pp 729-744
• Serial:
  • International Journal of Geomechanics
  • Volume: 13
  • Issue Number: 6
  • Publisher: American Society of Civil Engineers
  • ISSN: 1532-3641
  • EISSN: 1943-5622
  • Serial URL: http://ascelibrary.org/journal/ijgnai

Subject/Index Terms

• TRT Terms: Axle loads; Embankments; Finite element method; Load tests; Numerical analysis; Railroad tracks; Soil stabilization
• Subject Areas: Geotechnology; Railroads; I42: Soil Mechanics;

Filing Info

• Accession Number: 01500028
• Record Type: Publication
• Files: TRIS, ASCE
• Created Date: Nov 25 2013 10:02AM