01550209

Component

To protect the structure and restore a smooth riding surface, many airports repair deteriorating concrete pavements with an overlay of hot mix asphalt (HMA). Reflective cracking is a serious concern associated with the use of thin overlays but is not addressed in the current Federal Aviation Administration (FAA) Advisory Circular for asphalt concrete (AC) overlaid rigid pavements. This paper presents a comprehensive study to examine the crack initiation and propagation of a test HMA overlay with and without a strain relieving interlayer, and to evaluate the interlayer performance to retard thermally-induced reflection cracks. To achieve these objectives, three-dimensional finite element analyses (FEA) were first conducted to assess key structural parameters controlling the tension stresses at the overlay bottom. Next, laboratory tests were performed to characterized fatigue, fracture, and viscoelastic performance of the interlayer mixture. Finally, a test pavement was built, instrumented, and tested at the FAA National Airport Pavement Test Facility (NAPTF). Full-scale test data suggested that the strain relieving interlayer considerably improved the reflective cracking resistance of the HMA overlay. Inclusion of a 1-in.-thick interlayer between existing concrete slabs and the overlay extended overlay service life up to 15%. The intact interlayer had prevented spalling and moisture infiltration at the joint and therefore prolonged the structural integrity of the pavement. In addition, mixed-mode fracture and channeling were observed in the crack propagation. This paper provides extensive information in hopes of increasing awareness of the FAA’s contributions to the airport pavement research on reflective cracking.

This paper was sponsored by TRB committee AFD70 Pavement Rehabilitation. Alternate title: Evaluation of Strain Relieving Interlayer to Retard Thermally-Induced Reflective Cracking.

01550057

15-3236

English

24p

2015

Transportation Research Board 94th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Airport runways; Bituminous overlays; Finite element method; Hot mix asphalt; Laboratory tests; Pavement interlayers; Prototype tests; Reflection cracking; Rigid pavements; Service life

National Airport Pavement Test Facility

Stress relieving interlayers

Aviation; Design; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces

Transportation Research Board Annual Meeting 2015 Paper #15-3236

PRP, TRIS, TRB, ATRI

Dec 30 2014 1:05PM