Dynamic model and criteria indices of semi-rigid base asphalt pavement

Abstract

This paper presents a dynamic model of asphalt pavement by considering the characteristics of moving tyre load, viscoelastic performance of material and layered system of pavement. The pavement is defined as an infinite layered system with the tyre load moving at a constant speed, and asphalt concrete (AC) is characterised as a kind of visco-elastic material. Using the spectrum analysis method, a complex tyre load is decomposed into a series of harmonic loads. Based on the frequency characteristics of a linear system, a universal formulation pattern for differential visco-elastic constitutive relations is provided. And then, a model is set up to analyse the dynamic response of asphalt pavement under moving harmonic load, and then to extend to the arbitrary moving load according to the superposition principle of a linear system. The dynamic responses of seven typical semi-rigid base asphalt pavements are analysed using the model. Analysis results indicate that the tensional strain at the bottom of the AC layer and the vertical compression strain at the top of the roadbed are not suitable for key indices of the semi-rigid base asphalt pavement. The shearing strain at the bottom of the AC layer can be taken as a key index to evaluate the fatigue performance, and the vertical compression strain at the top of the pavement surface can be taken as a key index to evaluate pavement rutting, and the vertical shearing strain at the top of pavement surface can be taken as a key index to evaluate top-down crack.

Ensuring adhesion between the asphalt-concrete road surface and rigid base at the roadbed design stage

“…The model's grid is built using elements of a predominantly hexagonal shape. The elements' shape was selected on the basis of works [5,9,20,21]. An example of the estimation model is shown in Fig.…”

“…Macro defects [9][10][11] are also distributed in the volume of the material. It is known from [9,10,14,20] that the body that has macro defects can be considered as a quasi-homogeneous system within its base -the matrix. In this case, the idealization of the real environment in relation to its homogeneity, the solidity of isotropy do not lead to fundamental errors in calculations based on general solutions in elasticity theory [9,18,20,21].…”

“…It is known from [9,10,14,20] that the body that has macro defects can be considered as a quasi-homogeneous system within its base -the matrix. In this case, the idealization of the real environment in relation to its homogeneity, the solidity of isotropy do not lead to fundamental errors in calculations based on general solutions in elasticity theory [9,18,20,21]. The estimation model used to simulate the stressed-strained state of a roadbed structure is shown in Fig.…”

Viscoelastic dynamic response of asphalt pavement with imperfect interface bonding base on transfer matrix

“…The viscoelastic dynamic response of asphalt pavement is influenced by several factors, such as geometrical parameters, material properties, and boundary conditions of the pavement. The interface bonding condition is usually assumed to be perfect when an asphalt pavement model is established [1,2]. However, this is not consistent with the real situation, where the interface is not completely continuous.…”

“…Whether an asphalt pavement model can precisely describe the behavior of a pavement depends mostly on the rheological model of the asphalt layer. Kelvin, Maxwell, Venderpoel, and Burgers models are the classical models used to simulate asphalt concrete materials [1,21]. Other effective or modified models have also been developed [22].…”