The traffic load stress is defined as a factor of the expected traffic load (axle load), taking the maximum tensile stress fmax at test temperature Tf,max derived from the UTST into account. It is recommended to derive the traffic load stress ∆σ analytically, using a linear elastic model as a factor of traffic load as well as of the stiffness and thermal material properties of the pavement layers and their composition. For comparing surface course asphalts, a traffic stress of ∆σ = 1,6 MPa has been found to be appropriate.