Effect of Pavement Roughness and Transverse Slope on the Magnitude of Wheel Loads

Pavement distresses are assumed to occur uniformly along the left wheel path and right wheel path of the vehicles within a lane. However, there can be a significant difference in the magnitude of a particular distress between each of wheel paths due to transverse slope. Transverse slope significantly affects the magnitude of wheel load that is being transmitted to the top of pavement surface in each of the wheel paths. The magnitude of wheel load would be higher on the outer wheel path with reference to the median for a dual carriageway resulting in higher distresses. In a similar manner, rough pavement deteriorates at a much faster rate compared to smooth pavement as the magnitude of dynamic loads increases with increase in pavement surface roughness. Such effects are not taken into account in stress analysis and subsequent distress quantification. The focus of the current study is to quantify the magnitude of excess wheel loads due to the combined effects of pavement roughness and transverse slope. A fully loaded two-axle truck movement using TruckMaker software was simulated on a pavement surface by varying the pavement roughness and the transverse slope. Taking into account the initial roughness over a newly constructed pavement, the magnitude of axle load increased by 9% compared to the standard axle load. Further, the increase in magnitude of wheel load acting on the outer wheel path varied between 3.32 and 4.85% compared to the inner wheel path for a given pavement roughness profile by considering the standard range of transverse slopes.