Paper presented at the 31st Annual Southern African Transport Conference 9-12 July 2012 "Getting Southern Africa to Work", CSIR International Convention Centre, Pretoria, South Africa.
This paper proposes a methodology for assessing the damage imposed by the movement of wind turbine components on Texas’s highway infrastructure. The pavement damage associated with traffic resulting from site preparation was omitted from the scope of this study because reliable data characterizing the construction traffic were not available. The damage to the pavement structure was estimated using three primary distresses: rutting, longitudinal, and alligator cracking. In addition, the impact on the ride quality was also estimated. Pavement damage was evaluated using the Mechanistic Empirical Pavement Design Guide (MEPDG). The methodology adopted involved calculating the pavement distress due to the combined effect of the wind turbine and the design traffic relative to the design traffic only. This ensures that biases in the distress predictions obtained from the MEPDG will cancel each other out in each of the two scenarios. For the roughness estimate, the difference between the damage value due to the combined traffic and the design traffic only was evaluated and deemed as the damage indicator. The researchers observed that the increased pavement damage in the case of national highways was roughly 0.3 and 4 per cent irrespective of the distress mechanism. However, the pavement damage on state highways had a much more serious impact. The researchers observed that the relative damage imposed on the pavement structure from a roughness perspective was minimal. The additional damage imposed by the wind turbine truck traffic will translate into a reduction in pavement service life estimated at 9 per cent.
