United States Department of Transportation
ROSA P serves as an archival repository of USDOT-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by USDOT or funded partners.
As a repository, ROSA P retains documents in their original published format to ensure public access to scientific information.
[PDF-24.04 MB]
Details:
-
Creators:
-
Corporate Creators:
-
Corporate Contributors:
-
Subject/TRT Terms:
-
Resource Type:
-
Geographical Coverage:
-
Edition:November 2017 to January 2021
-
Corporate Publisher:
-
Abstract:The Florida Department of Transportation (FDOT) has experienced roadway worms, or blistering of flexible pavements, for several decades. A literature review indicated that the distress (also referred to as ripples and distortions) generally occurs due to moisture or other gas-forming substances trapped in between two layers of asphalt concrete (AC), which may vaporize and expand in volume under hot environments. Forensic investigations were conducted on five Florida roadway sections that exhibited the distress to identify the causes and contributing factors of roadway worms and to assess the impact of the worm distress on pavement performance. Field and laboratory test results indicated worm distresses on each site are associated with deterioration due to the presence of moisture within the AC layers and at the interface of the upper two AC lifts. The deterioration was more pronounced in the dense-graded AC surface course layers and included segregation, excessive air voids, stripping, and interface debonding with underlying AC layers, as confirmed by laboratory test results. Although the modulus degradation was greater for the top lift, it was observed in both the top and the bottom lift AC. Simulation of pavement response and performance showed that the worm-distressed sections exhibit increased level of pavement response (i.e., deflections and strains) and a significant reduction in predicted pavement life (i.e., 62% to 92% reduction under top-down cracking mode). Strategies are recommended for preventing the occurrence of worm distress and rehabilitating pavements with worm distress. The findings of this study do not support any recommended design changes.
-
Format:
-
Funding:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type:
