By Tom Kuennen, Contributing Editor, Better Roads (June 2011)
Diamond grinding of Portland cement concrete pavements and micro-milling of bituminous asphalt pavements are superficially similar in concept, but that’s just about the only thing they have in common.
Diamond grinding of aging Portland cement concrete (PCC) pavements renews the pavement’s skid-resistance, and provides a smoother-riding pavement. And the resulting smoother profile reduces dynamic loading on the pavement, thus extending its service life.
On the other hand, micromilling, or fine-tooth milling – using conventional cold mills with fine-tooth drums and hardened teeth – can remove imperfections from an asphalt surface and prepare it for a super-smooth thin asphalt overlay in a manner superior to conventional cold milling. In some cases, it can even be used instead of grooving or grinding pavements.