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are not fully known. Translating these dynamic loads to pavement wear effects is thereforedifficult.If complete absence of spatial repeatability is assumed, the dynamic loads are randomlydistributed on the road, and each spot will be subjected to the full spectrum of dynamicloads. Then the effect of changes in DLC could be calculated by calculating the totalpavement wear effect of each probability distribution of the dynamic wheel loads(corresponding to each DLC, shown in Figure 4.70), and expressing these as a relativenumber.2015315/70R22.5495/45R22.5Frequency [%]10500 10 20 30 40 50 60 70Wheel load [kN]Figure 4.70 - Calculated wheel load distributions on even road at 80 km/h.Eisenmann (1975) published a formula, quantifying road stress in a dynamic road factor(ν) as a function of DLC:2 4ν = 1+6s + 3s(s = DLC).This assumes that there is no spatial repeatability. Using this formula, the dynamic roadfactors were calculated for the measured DLC’s at the shaker table and the Virttaa test site.These are shown in Table 4.57.Table 4.57 - Calculated dynamic road factors (ν) for 315/70R22.5 and 495/45R22.5tyres; shaker table simulations of fair, poor and bad road, and Virttaa sitemeasurements.Road315/70R22.5495/45R22.5Factor Factor [%] Factor Factor [%]Fair road 1.012 100 1.012 99.9Poor road 1.027 100 1.023 99.6Bad road 1.059 100 1.054 99.6Virttaa 1.012 100 1.009 99.7130version 29 November 2001