Simulating the Impact of Vehicle Speed on the Life of Bituminous Pavement

Due to the visco-elastic nature, the performance of flexible pavements depends on temperature and loading conditions. This study investigates the influence of different speeds of vehicle and binder type on stiffness modulus and the corresponding pavement life. The filed data was collected from the pavement section at Bukit Mertajam, Penang, Malaysia. The data were used to determine the stiffness of binder and corresponding stiffness of wearing and binder courses at different vehicle speeds (30, 50, 70 and 80 km/h) using analytical equations. The data of layer properties (stiffness and poison's ratio) and axle loading (wheel load, tyre configuration) were incorporated in BISAR software to determine the horizontal tensile strain at bottom of binder layer and vertical compressive strain at top of subgrade. The strains were then used to predict pavement life passed on fatigue and rutting failure criteria. It was concluded that increasing the speed of the vehicle (from 30 km/h to 80 km/h) causes about 24 increase in stiffness modulus of wearing course. Similarly, asphalt mixture with Pen 80/100 grade bitumen has a lower stiffness modulus than Pen 60/70 grade bitumen. Furthermore, reducing vehicle speed (i.e., increasing loading time) causes a reduction in fatigue and rutting life of the pavement. Therefore, it is required to consider the speed of the vehicle while designing flexible pavement in addition to other mixed design considerations. © Published under licence by IOP Publishing Ltd.