Steve Brown's letter regarding early life skidding resistance of stone mastic asphalts (NCE 14 February) raised many important issues concerning the slipperiness of newly laid road surfacings which have come to light as a consequence of the study carried out by TRL for Derbyshire County Council.
Since I was involved in the project from the outset, it is only fair to point out that neither TRL nor Derbyshire County Council claims to have answers to these important questions. Our purpose in putting this study into the public domain is to raise awareness of the issues.
We fully recognise the limitations of this work. We ourselves have asked the same questions - does it apply to other bituminous surfacings, does negative/positive texture have an effect, what is the effect of different aggregates, different binders, different fillers, different suppliers etc.
But these issues are far beyond the scope of one local authority to research.
TRL/HA/CSS are currently undertaking research into early life skidding resistance of new surfacings. Can these issues please be looked at for us?
JohnBrewster, Environmental Services, Derbyshire County Council, john. email@example.com. uk