01373780

Component

The Florida Department of Transportation (FDOT) recently investigated the effect of an asphalt rubber membrane interlayer (ARMI) on instability rutting with a controlled accelerated pavement testing (APT) program and theoretical modeling. An ARMI is a specific type of stress absorbing membrane interlayer (SAMI) constructed of a single application of a No. 6 stone seated into a layer of asphalt rubber binder. Florida first experimented with an ARMI to mitigate reflection cracking more than 30 years ago. However, concerns have risen that an ARMI may contribute to instability rutting. APT test sections included 2, 3 and 4 inch thick overlays of an ARMI. A 4 inch overlay without an ARMI and a new 2 inch thick asphalt pavement were also included in the study as control sections. The APT investigation and Finite Element model showed that an ARMI significantly increases the potential of instability rutting when slow moving heavy tire loads and elevated temperatures are present. These conditions are common during summer months at intersections, toll plazas and other roadway features that prohibit increased speeds. Based on the findings of this study, an ARMI is not recommended on pavements subjected to slow moving and concentrated truck loads. Alternative techniques to mitigate reflection cracks are recommended. This paper presents a description of the test program, the data collection efforts, and the subsequent analysis and findings.

This paper was sponsored by TRB committee AFD60 Flexible Pavement Design

01362476

12-3536

English

15p

2012

Transportation Research Board 91st Annual Meeting

Digital/other

Figures; References; Tables

Asphalt rubber; Axle load force; Overlays (Pavements); Reflection cracking; Rutting; Slow moving vehicles

Highways; Pavements; I22: Design of Pavements, Railways and Guideways

Transportation Research Board Annual Meeting 2012 Paper #12-3536

TRIS, TRB

Feb 8 2012 5:17PM