TRANSVERSE CRACKING PROGRESSION IN ASPHALT SHOULDERS ADJACENT TO CONCRETE PAVEMENTS

摘要

The shoulder forms an integral part of the highway pavement system. It promotes safe traffic operations and provides lateral support for the adjacent mainline pavement when properly designed and maintained. A literature survey conducted on shoulders suggests that, the design procedures currently in use by State Highway Agencies (SHAs) have developed gradually through experience rather than from a rational pavement design approach. Consequently, most shoulders may be considerably under-designed and have resulted in unsatisfactory performance. This paper presents an examination of transverse cracking propagation on in-service asphalt shoulders adjacent to dowel-jointed plain concrete pavements in Wisconsin. On the basis of the examination, it is concluded that a minimum asphalt surface thickness of 100 mm (4 in.) combined with sealing of the longitudinal joint between the concrete pavement and the shoulder, will minimize the extent of transverse cracking. Using a crushed aggregate base course as opposed to an open-graded base course can minimize the severity of transverse cracking. In addition, using a wider asphalt shoulder and sealing of the longitudinal joint can minimize the combination of transverse cracking severity and extent.