Chip seals have been widely used as a pavement maintenance surface treatment due to its competitive cost and construction time. Recently, the research team developed a rubberized chip seal where natural aggregate is replaced with crumb rubber obtained from recycled tires. During this study, a total of 108 laboratory specimens and a field chip seal section with different crumb rubber replacement ratios were investigated. Aggregate macrostructure, retention, and skid resistance were measured. The crumb rubber showed a remarkable performance in aggregate retention measured using the Vialit and Pennsylvania tests. The values of the mean texture depth of rubberized chip seal specimens were significantly higher than those of the conventional chip seal. Finally, while a reduction in the British Pendulum Number (BPN) was recorded with an increase in the crumb rubber replacement ratio immediately after construction, after a period of more than a year of service life in the experimental section road, the rubberized chip seal segments recorded a much higher BPN compared to that of the conventional chip seal segment. Furthermore, it is recommended also to increase the curing time for chip seal, regardless of aggregate type, to at least six hours to improve the performance of the chip seal.


Civil, Architectural and Environmental Engineering


Missouri Department of Transportation


PREPARED FOR: Missouri Department of Transportation Construction and Materials Division Research Section

Funding: MoDOT project # TR201804

Final Report (September 2017-December 2018)

Keywords and Phrases

Chip seals; Implementation; Rubber

Report Number

CMR 18-012

Document Type

Technical Report

Document Version

Final Version

File Type





© 2018 Missouri University of Science and Technology, All rights reserved.

Publication Date

December 2018