Flexible pavement responses to different loading amplitudes considering layer interface condition and lateral shear forces

Abstract

A three-dimensional (3D) finite element (FE) parametric study was conducted to quantify the viscoelastic pavement responses due to different tire configurations: dual and wide-base tires, at three temperatures (5, 25 and 408C) and two speeds (8 and 72 km/h). Three factors affecting pavement responses were investigated: type of moving wheel loading amplitude (continuous, trapezoidal), interface layer condition (simple-friction and elastic-stick models) and lateral surface forces. It was found that the continuous loading amplitude, which has an asymmetric stress magnitude and considers the difference between the entrance and exit of the tire, can simulate pavement responses to moving wheel vehicular loading more accurately than the currently used trapezoidal loading amplitude. The elastic-stick model resulted in a sensible improvement for predicting pavement responses to dual tire, while the simple-friction model is more comparable to field measurements in the case of the wide-base tire. The shear force was found to positively improve the prediction of the calculated strain at the bottom of the wearing surface and to a lesser degree at the bottom of the hot mix asphalt (HMA) base layer. This study concludes that using continuous loading amplitude and non-uniform pressure distribution to simulate a moving wheel, surface shear forces and appropriate layer interface friction may significantly improve the capability of FE models to predict pavement response to vehicular loading. Results have been successfully validated against field measurements.

Effects of pavement texture on pavement friction: a review

“…The challenges for a FEM simulation result from large deformation of tyre rubber, transient contact conditions, intricate structures of tyres and strong nonlinear friction properties. Many authors utilised 3-dimentional FEM programs to simulate the interaction effects between tyre rubber and pavement surface on the response of pavement surface (Zaghloul and White, 1993;Uddin et al 1994;Yoo et al, 2006). Although the FEM simulations have presented a successful application in pavement analysis, most of these numerical simulations are still unsuitable for application to practical analysis, because they just served their originators adequately in attaining their limited objectives.…”

Numerical comparison of flexible pavement dynamic response under different axles

“…Therefore, to simulate a moving load with different speeds, the tyrepavement contact area could progressively be shifted along the wheel path in the direction of traffic until a single tyre pass is completed (Yoo 2006, Liao 2007, Wang 2011. Five vehicle speeds considered were 20, 40, 60, 80 and 100 km/h.…”

“…For predicting the time-dependent response using FEM, to simplify the analysis of flexible pavement by using FEM, linear elastic and time-independent material behaviour for the base and subgrade layer and linear viscoelastic material property for the asphalt layer were used (Yoo 2006, Kim et al 2009, De Araújo Jr. et al 2010, Wang 2011, Kim 2011. It is well known that base and subbase soils are not elastic and result in permanent deformation under stationary loads.…”

Effects of Sensor Location on Dynamic Load Estimation in Weigh-in-Motion System

“…However, the real contact area is not a complete circle. Especially, in the case of wide-base tire, the contact area gets more oriented in the width and less in length comparing with that of conventional tires [ 30 ]. In our work, tire contact area is assumed to be a rectangle with a constant width.…”