Effects of Cross-Anisotropy and Temperature on Pavement Stress-Strain Responses under Dynamic Loading

This study investigates the effects of cross-anisotropy and temperature on asphalt pavement’s stress-strain responses under moving wheel loads. To facilitate the study, a dynamic Finite Element Model (FEM) of an instrumented pavement section on Interstate-40 (I-40) near Albuquerque, New Mexico, is developed in ABAQUS incorporating depth-temperature variations in the asphalt concrete (AC) layer under a truck wheel loading. Cross-anisotropy in the model is defined as the ratio of horizontal to vertical modulus (n-value) of the AC. Field compacted AC cores were collected from the instrumented pavement section and tested in the laboratory for n-values and viscoelastic parameters as FEM model inputs, which are incorporated in the FEM model using the User Defined Material (UMAT) functions in ABAQUS. The model is validated using field measured deflections and strains values under Falling Weight Deflectometer (FWD) loads. The validated model is used for a parametric study by varying n-values of AC material under different pavement temperatures. It is observed that the horizontal tensile strain at the bottom of the AC layer decreases as the n-value approaches 1.0 (isotropy). It indicates that the horizontal tensile strain decreases as the horizontal modulus of the AC increases. It is also observed that the vertical strains on top of pavement layers decreases with an increase in n-value. It indicates that increase in horizontal modulus of the AC leads to decrease in the vertical strains of pavement layers. The parametric study based on pavement temperature variation shows that horizontal tensile strain at the bottom of the AC layer as well as vertical strains on top of AC, base, subbase, and subgrade are highly sensitive to temperature variation in the AC layer.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFD60 Flexible Pavement Design.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Ahmed, M U
  • Rahman, A
  • Islam, M R
  • Tarefder, R A
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References; Tables;
• Pagination: 18p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Asphalt concrete; Asphalt pavements; Dynamic loads; Falling weight deflectometers; Finite element method; Interstate highways; Strain (Mechanics); Stresses; Temperature; Tension; Validation
• Identifier Terms: ABAQUS (Computer program)
• Uncontrolled Terms: Cross-anisotropy; Vertical strain
• Geographic Terms: Albuquerque (New Mexico)
• Subject Areas: Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways;

Filing Info

• Accession Number: 01553022
• Record Type: Publication
• Report/Paper Numbers: 15-5710
• Files: TRIS, TRB, ATRI
• Created Date: Feb 9 2015 4:31PM