Validation and Improvement of Pavement ME Flexible Pavement Roughness Prediction Model Using Extended LTPP Database

International Roughness Index (IRI) is a pavement performance indicator which reflects not only pavement condition but also ride quality and comfort level of road users. Since 2004, the Mechanistic-Empirical Pavement Design Guide (MEPDG), now known as Pavement ME design, considered IRI as one of the design criteria for both flexible and rigid pavements. The latest MEPDG IRI predictive model for flexible pavements was based on the Long-Term Pavement Performance (LTPP) database (as of 2006). The model predicts IRI as a function of distresses predicted by the MEPDG software, namely, initial IRI (IRI just after construction), longitudinal and alligator fatigue cracking, transverse cracking, average rut depth and site factor. This model has a coefficient of determination (R²) of 0.56 based on the 1926 LTPP observations used for the model development. The aim of this paper is to validate the current Pavement ME design IRI model for flexible pavements based on the extended LTPP database which now has 10 more years of data compared to 2006 data. The model validation using the extended database resulted in a lower R² of 0.45. Moreover, the model was calibrated using the extended database and resulted in an R² of 0.50. Analysis of the data revealed that longitudinal cracking and the site factor were not significant factors Thus, a revised model was proposed for IRI prediction as a function of age, initial IRI, transverse cracks, alligator fatigue cracks and standard deviation of the rut depth. The proposed model yielded a relatively higher R² of 0.57.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFD60 Standing Committee on Design and Rehabilitation of Asphalt Pavements.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Abd El-Hakim, Ragaa
  • Abd El-Aziz, Nader E
  • El-Badawy, Sherif M
  • Afify, Hafez A
• Conference:
  • Transportation Research Board 96th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2017-1-8 to 2017-1-12
• Date: 2017

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 16p
• Monograph Title: TRB 96th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Fatigue cracking; Flexible pavements; Rutting; Validation
• Identifier Terms: International Roughness Index; Long-Term Pavement Performance Program; Mechanistic-Empirical Pavement Design Guide
• Uncontrolled Terms: Coefficient of determination
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01622837
• Record Type: Publication
• Report/Paper Numbers: 17-02203
• Files: TRIS, TRB, ATRI
• Created Date: Jan 23 2017 4:05PM