Influence of thin water film on skid resistance

Yannick Beautru (1) , Véronique Cerezo (2) , Minh Tan Do (1) , Malal Kane (1)

1 IFSTTAR/IM - Département Infrastructures et Mobilité
2 CETE de Lyon - Centre d'études techniques de l'équipement de Lyon

Most of past researches on the skid resistance/road wetness relationship deal with thick water depths (> 1mm). Questions remain as to the variation of skid resistance with thin water films and the transition between the dry state and the so-called “damp” or “humid” state at which the skid resistance drop can be as high as 30-40%. This paper deals with a theoretical and experimental assessment of the friction/water depth relationship. The main objective is to estimate local water depths trapped between the tire and the road asperities and to define a so-called “critical” water depth which can be used for driver assistance systems. Tests are performed in laboratory and on test tracks. It was found that the friction-water depth curves have an inverse-S shape and present an initial constant-friction part before decreasing to a minimum value. A “critical” water depth, defined as the water depth above which the friction coefficient collapses significantly, is determined from observed frictionwater depth curves. Influence of test speed and road surface texture on critical water depth is discussed.

Mots clés: ADHERENCE; FILM D'EAU; HAUTEUR D'EAU; ADHESIVITE

Domaines: Mécanique [physics.med-ph]

Yannick Beautru, Véronique Cerezo, Minh Tan Do, Malal Kane. Influence of thin water film on skid resistance. SURF 2012 (7th Symposium on Pavement Surface Characteristics), Sep 2012, France. 15p, tableaux, ill., schémas, graphiques, bibliogr. ⟨hal-00851144⟩