Ground-Penetrating Radar for Cold In-Place Recycled Road Systems

Abstract

Saskatchewan Department of Highways and Transportation (SDHT) is responsible for maintaining approximately 6500 kilometers of northern gravel surfaced roads. Many of these northern gravel roads are built on poorly graded sand subgrades and may contain protruding bedrock and/or large boulders. Because of this, washboarding, protruding rocks, rutting and potholes are common performance problems of many northern gravel roads. Routine blading of these roads is often ineffective because unstable sand does not maintain its shape and compaction, protruding bedrock and boulders damage motor grader blades, boulders may become dislodged leaving holes in the road, and dislodged boulders are a safety hazard when windrowed along road side-slopes. Clay capping and base stabilization have been used to provide a stable wearing surface, cover protruding bedrock and large boulders, and reduce traffic dust. However, the long-term performance of clay capping and base stabilization can be highly variable and the associated costs can make these conventional solutions untenable. As a result, SDHT investigated the use of in-place rock crushing and stabilization/modification for northern gravel roads with significant proportion of boulders in the grade using a rotomixer/stabilizer. Based on the findings of this study, inplace rock crushing and stabilization/modification is a technically feasible solution for eliminating protruding bedrock and boulders contained near the surface. However, in-place crushing of boulders with unconfined compressive strengths over 50,000 psi resulted in significant damage to the rotomixer mandrel resulting in an approximate cost of just under $13,684 CDN per kilometer. in situ rock crushing with subgrade stabilization and double seal was found to cost approximately $52,017 CDN per kilometer. Berthelot, Gerbrandt, Safronetz, and Sparks.

NDT Transportation

“…divide road into homogenous sub-sections, or to check if the pavement is thick enough for recycling milling and (4) for quality control purposes (see Briggs et al, 1991;Fernando et al, 1994;Saarenketo, 1997;Saarenketo and Roimela, 1998;Scullion and Saarenketo, 1998;Berthelot et al, 2001;Maser, 2002b;Saeed and Hall, 2002;Sebesta and Scullion, 2002a,b;Hugenschmidt, 2003;Noureldin et al, 2003). divide road into homogenous sub-sections, or to check if the pavement is thick enough for recycling milling and (4) for quality control purposes (see Briggs et al, 1991;Fernando et al, 1994;Saarenketo, 1997;Saarenketo and Roimela, 1998;Scullion and Saarenketo, 1998;Berthelot et al, 2001;Maser, 2002b;Saeed and Hall, 2002;Sebesta and Scullion, 2002a,b;Hugenschmidt, 2003;Noureldin et al, 2003).…”

Measurement of the Promoting Effect of Complex Conditions on the Adhesion Development in Curing Process of Cold Recycling Mixture with Emulsified Asphalt

“…Due to its increasingly widespread application worldwide [8][9][10][11][12][13][14][15], numerous studies have shown that the process of curing and adhesion development of CR mixtures are key issues in this field. The development of adhesion is a prerequisite for its strength formation, and its strength is an important basic mechanical indicator in its application.…”