01662653

Component

In 2013, the Minnesota Department of Transportation (MnDOT) conducted a preliminary study that identified high air voids in underlying asphalt pavements as the main cause of stripping under chip seals. This paper details a research project sponsored by the Minnesota Local Road Research Board (LRRB) to follow-up on and extend the 2013 MnDOT study. The research included observation, testing, and analysis of 18 chip-sealed roadways in eight cities and counties in Minnesota. Field studies included surveys of pavement density (using ground- penetrating radar and nuclear gauge tests). Laboratory tests were also conducted to assess permeability, stripping, tensile strength ratio, asphalt film thickness, and mix properties. A major outcome of the research was the inability to verify the earlier MnDOT finding that high air voids were a cause of stripping under chip seals. The study also observed no direct relationship between incidence of stripping and asphalt pavement density and stripping. In addition, the study found no evidence to support correlations between incidence of stripping and site/supplier data (e.g. bituminous mixture, contractor, geographic location, or year of construction). Conclusions and recommendations from this broad, detailed exploration of stripping in chip sealed pavements are presented in the paper to inform city and county engineers on the use of chip seal treatments in municipal roadways.

This paper was sponsored by TRB committee AFD60 Standing Committee on Design and Rehabilitation of Asphalt Pavements. Alternate title: Stripping Under Chip Sealed Pavements in Minnesota.

18-00071

English

16p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Air voids; Asphalt pavements; Chip seals; Field studies; Laboratory tests; Stripping (Pavements)

Minnesota Department of Transportation

Minnesota

Highways; Pavements

Transportation Research Board Annual Meeting 2018 Paper #18-00071

TRIS, TRB, ATRI

Jan 8 2018 10:03AM