1. PhD Student, Division of Highway Engineering, Royal Institute of Technology, S-100 44 Stockholm, Sweden (corresponding author). E-mail: robert.lundstrom@byv.kth.se
2. Professor, ENTPE, DGCB Rue M. Audin, 69518 Vaulx en Velin, France. E-mail: herve.dibenedetto@entpe.fr
3. Professor, Division of Highway Engineering, Royal Institute of Technology, S-100 44 Stockholm, Sweden. E-mail: ulf.isacsson@byv.kth.se