EVALUATION OF INDIRECT TENSILE TEST FOR DETERMINING THE STRUCTURAL PROPERTIES OF ASPHALT MIX. FINAL REPORT

Engineering characterization of Louisiana's asphaltic concrete mixtures using the indirect tensile test was the focus of a recent comprehensive research program sponsored by the Louisiana Transportation Research Center (LTRC). Large variations in test results were observed between similar specimens. These variations were attributed to variable aggregate orientation, compaction procedure and the test device. A new indirect tension device, developed by Michigan State University and further modified by LTRC, was fabricated locally and used in order to reduce the test variability. The objective was to evaluate the repeatability and performance of the new modified indirect tension device. Two test factorials were designed to assess the devices' performance and repeatability. The first was statistically designed to examine the variation of several test parameters for a specific asphaltic concrete mixture between the modified and the current LTRC test devices. The second was designed to investigate the variation in results between the modified and current test devices due to materials properties. Mechanical tests conducted were the indirect tensile strength test, the diametral resilient modulus test, and the indirect tensile creep test. Phase I of this research presents the effect of the test devices, deformation measurement system, and operator error on the mechanical properties of a specific asphalt concrete mixture. Phase II shows the influence of mixture type, asphalt cement source, and compaction effort on the same mechanical properties. The results indicated the following: use of two LVDTs to measure vertical deformations has reduced variation in test results; both test devices provided repeatable results; mechanical properties were not significantly different due to operator error; mechanical properties measured with the modified test device were significantly different than those measured with the existing test device; the modified test device can better capture the temperature effect on the resilient modulus than the existing test device; and resilient modulus and Poisson's ratio were significantly different between mixture types.

• Corporate Authors:

  Louisiana State University, Baton Rouge

  Department of Civil and Environmental Engineering
  Baton Rouge, LA  United States  70803

  Louisiana Transportation Research Center

  4101 Gourrier Avenue
  Baton Rouge, LA  United States  70808

  Federal Highway Administration

  Office of Technology Applications, 1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • West, R C
  • Page, G C
  • Murphy, K H
• Publication Date: 1992-8

Language

• English

Media Info

• Pagination: 94 p.

Subject/Index Terms

• TRT Terms: Asphalt concrete; Creep tests; Mechanical properties; Modulus of resilience; Performance; Poisson distributions; Poisson ratio; Structural analysis; Temperature; Tension tests; Testing equipment; Thermal stresses
• Uncontrolled Terms: Indirect tensile test; Repeatability; Structural properties
• Subject Areas: Highways; Materials; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00675289
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Report/Paper Numbers: FHWA-SA-94-021
• Files: TRIS, USDOT
• Created Date: Mar 16 1995 12:00AM