The use of finite element methods for verifying the choice of elastic layer models adopted in a back-analysis model for pavement overlay design

Verification of the linear layer models adopted in the back-calculation model EFROMD2 has been carried out by comparing the pavement response calculated with FEM and that back-calculated from FEM deflection bowls with the EFROMD2 Linear Models. EFROMD2 could predict the non-linear variation of granular and subgrade moduli with increasing depth. It also allowed some corrections for variation of granular and subgrade moduli in the radial direction by considering the materials as anisotropic. The comparison of the moduli back-calculated with the EFROMD2 Linear Models and the FEM results indicated significant differences between the EFROMD2 Linear Models. The current anisotropic model adopted by NAASRA (EFROMD2 LM1) appeared to produce the highest difference in moduli, whereas the EFROMD2 LM3 (with modulus ratio for the subgrade of less than 1) produced the lowest difference in moduli. However, it is to be noted that comparisons with the EFROMD2 solutions are on the basis of their vertical moduli. The comparison between the pavement response back-calculated with the EFROMD2 Linear Models and that calculated with FEM also indicated significant differences between the EFROMD2 Linear Models. Again the NAASRA model (EFROMD2 LM1) appeared to produce the highest differences in surface deflection, in depth deflection and in vertical strain; whereas the EFROMD2 LM3 produced the lowest difference in pavement response. However, it has also been found that the difference in pavement life predicted by FEM and EFROMD2 could be more than 100 per cent for some pavement configurations. Therefore, further investigation and comparative studies are still necessary in order to make any conclusive suggestion on what linear models should be used for back-calculating elastic moduli from pavement deflection bowls.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0869340336
• Authors:
  • Vuong, B
• Conference:
  • International Conference on Finite Element Methods, 6th, 1991, Sydney, Australia
• Publication Date: 1991

Language

• English

Media Info

• Pagination: 508-21
• Serial:
  • Volume: 2

Subject/Index Terms

• TRT Terms: Backcalculation; Finite element method; Mathematical models; Overlays (Pavements); Pavement design; Pavement layers
• ATRI Terms: Back analysis; Finite element method; Modelling; Overlay; Pavement design; Pavement layer
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 01431781
• Record Type: Publication
• Source Agency: ARRB
• ISBN: 0869340336
• Files: ATRI
• Created Date: Aug 24 2012 4:41PM