| Advancing technology has changed the configuration and load carrying capacities of trucks. Pavement engineers need more accurate methods to allow for these changes when they design and manage pavements. Considerable past research is available to calculate response of pavement structures for smooth pavements and static wheel forces. However, comparatively little work has been done to calculate the pavement response due to vehicle dynamics on rough pavements.;This research analyzes interaction between pavement and vehicle characteristics that affect pavement fatigue damage. For the purpose of analysis, computer models simulated truck behavior on road profiles of various roughnesses to produce truck load histories. VESYS generated pavement strain influence functions. Load histories and strain influence functions were combined to produce pavement strain histories and strain ranges. Strain range histories were passed through a fourth power damage function to calculate pavement fatigue damage and cost per pass of truck.;The research considered vehicle speed, axle spacing, individual axle suspensions, tire contact area, tire pressure, gross vehicle weight, heaviest axle, axle loads, wear course thickness, pavement roughness, and pavement cost. Charts, tables, and equations were calculated that demonstrate the impact each variable has on pavement damage and cost. Pavement fatigue ESALs were developed for various axle load and axle spacing combinations using strain influence functions. Methods were developed to calculate fatigue damage due to any truck moving on a pavement of any roughness at any speed. |
