Predictive method for evaluation of pavement rutting

Pavement rutting not only decreases the road service life but also creates a danger for the security of road users. In recent years, pavement rutting rate has increased significantly due to constant traffic intensity increment. It is well known that the increase in heavy vehicles flow, transported load, tyre pressure and the use of single tyres instead of dual tyres induce considerable pressure within bituminous layers. Due to these solicitations, bituminous layers can quickly attain their permanent deformation limit resistance and this phenomenon can lead to a pavement depression, located in the tyre- road contact surface. The purpose of this paper is to present a methodology to estimate the rutting of bituminous pavements and to be able to predict the rutting risk considering the results obtained with the LPC traffic simulator and taking into account the traffic and environmental characteristics. The traffic characteristics are represented by the total heavy traffic expressed in equivalent single axle loads (ESAL) passed on the pavement during the service period and the speed adopted by these heavy vehicles on the considered section. The environmental characteristic is represented by the pavement temperature at 2 cm depth. The developed model gives rut depths values after having determined material and site characteristics and presents a very good correlation coefficient giving very satisfactory results in its verification phase with additional materials.