This article addresses the question of whether the viscoelastic behavior of asphalt pavements, as part of the factors that impact the rolling resistance, might lead to substantially higher energy consumption of road traffic, as compared to non-dissipative pavements. In the context of sustainable development (fuel consumption, gas emission), this is a current issue for the pavement design community. This problem is tackled by a theoretical approach which consists in computing the structure-induced rolling resistance (SRR) for a vehicle by using the mechanical response of a layered viscoelastic medium excited by moving loads (i.e. tires of the vehicle). The structure-induced power dissipation is shown to be proportional to the integral over contours of the applied loads of the pavement deflection, times the outward normal to these contours. Following the developed approach, the determination of the SRR force engendered by the structure-induced dissipation is obtained from the computation of the deflection of the viscoelastic pavement to an assumed pressure distribution. Such an approach applied to a thick asphalt pavement allows the SRR for a typical road structure to be evaluated as a function of temperature and speed. A non-dimensional analysis is also presented to extend the results to some other contexts. Under the assumptions made for the derivation of the SRR, the main conclusion of the case study is that the extra fuel consumption for a vehicle resulting from the viscoelastic behavior of asphalt pavements is small.

/pdf/evaluation-of-the-structure-induced-rolling-resistance-srr-24tvu661m9.pdf

Evaluation of the structure-induced rolling resistance (SRR) for pavements including viscoelastic material layers

https://hal.archives-ouvertes.fr/hal-00561917/document

Influence of sliding interfaces on the response of a layered viscoelastic medium under a moving load

Evaluation of properties and fatigue life estimation of asphalt mixture modified by organophilic nanoclay

Dynamic inelastic analysis of 3-D flexible pavements under moving vehicles: A unified FEM treatment

This report describes the efforts undertaken to develop a novel self-powered strain sensor for continuous structural health monitoring of pavement systems under the Federal Highway Administration. Efforts focused on designing and testing a sensing system that consists of a novel self-powered wireless sensor capable of detecting damage and loading history for pavement structures. The developed system is based on the integration of a piezoelectric transducer with an array of ultra-low power floating gate computational circuits. A miniaturized sensor was developed and tested. The sensor is capable of continuous battery-less monitoring of strain events integrated over the occurrence duration time. The work conducted under this project resulted in the following: A. The development of a sensor that has the following attributes: (1) Self-powered, continuous, and autonomous sensing; (2) autonomous computation and non-volatile storage of sensing variables; (3) small size such that it can be installed using existing installation procedures that are accepted by State highway agencies and will not constitute a major disruption to current practices; (4) wireless communication to eliminate the need for embedding wires in the pavement structure and the use of fixed data acquisition systems on the side of the road; (5) robustness to withstand harsh loading and environmental conditions during initial construction and throughout the life of the pavement; and (6) the ability of integration in large-scale sensor networks. B. The manufacturing of the sensor electronics and the characterization of their basic functionalities in a laboratory setting. C. The design and characterization of the self-powering scheme based on piezoelectric transduction. D. The design and testing of a robust packaging system to withstand loading and environmental conditions for field implementation. E. The development of a sensor-specific data interpretation algorithm for predicting remaining fatigue life of a pavement structure using cumulative limited compressed strain data stored in the sensor memory.

https://rosap.ntl.bts.gov/view/dot/34779/dot_34779_DS1.pdf

Smart Pavement Monitoring System

As shown by strains measured on full scale experimental aircraft structures, traffic of slow-moving multiple loads leads to asymmetric transverse strains that can be higher than longitudinal strains at the bottom of asphalt pavement layers. To analyze this effect, a model and a software called ViscoRoute have been developed. In these tools, the structure is represented by a multilayered half-space, the thermo-viscoelastic behaviour of asphalt layers is accounted by the Huet-Sayegh rheological law and loads are assumed to move at constant speed. First, the paper presents a comparison of results obtained with ViscoRoute to results stemming from the specialized literature. For thick asphalt pavement and several configurations of moving loads, other ViscoRoute simulations confirm that it is necessary to incorporate viscoelastic effects in the modelling to well predict the pavement behaviour and to anticipate possible damages in the structure.

https://hal.archives-ouvertes.fr/hal-00421048/document

ViscoRoute 2.0 A Tool for the Simulation of Moving Load Effects on Asphalt Pavement

The travelling of high-speed trains on ballasted tracks creates geometrical disorders, which are found to evolve fast with the traffic loading as compared to the disorders observed on usual speed rail tracks. These high-speed rail lines thus require frequent maintenance associated to high direct and indirect costs. The circumstances leading to such disorders are not well understood and must be studied to allow the definition of design methods that minimize them. Among the factors that may favor the development of geometrical disorders, inertia forces within the railway structure are suspected to play an important role. In that context, this paper presents a method to compute the dynamic response of the structure under moving loads and thus to analyze the combined effects of stress and acceleration on the ballast layer. The developed method is based on continuum mechanics and relies on the decomposition into loading waves of the distribution of vertical stresses at the surface of the medium. This distribution results from loads applied on the rails and is computed by consideration of the system made up of the rails, the sleepers and the structure. The global response is obtained by recombination of the contributions of the loading waves, each of which moves at a different speed. This method is implemented in a numerical program which is used to study the dynamic response of a three-layer structure. It is shown that the influence of the load speed on the deflection and the vertical stress within the ballast layer is relatively small by comparison to that on the vertical acceleration. In some parts of the structure, small vertical stresses are associated to significant vertical accelerations oriented downward. This combination is suspected to promote the development of instabilities within the ballast layer.

Modeling of the dynamic response of ballast in high-speed train structures

Viscoroute 2.0: a tool for the simulation of moving load effects on asphalt pavement

Cet article presente une methode qui permet de calculer la reponse dynamique d'une structure ferroviaire sur la base d'une approche quasi-statique ne necessitant pas de discretisation temporelle. Le systeme complet compose des rails, des traverses et de la structure est periodique dans la direction du roulement. Les dimensions spatiales de la structure sont supposees semi-infinies. La methode proposee repose sur la decomposition de la distribution de contraintes a la surface de la structure en ondes de chargement se deplacant a des vitesses differentes. L'utilisation de cette methode est illustree sur un exemple numerique. (A).

https://hal.archives-ouvertes.fr/hal-00906779/document

Olivier Chupin

Papers

ViscoRoute 2.0 A Tool for the Simulation of Moving Load Effects on Asphalt Pavement

Modeling of the dynamic response of ballast in high-speed train structures

Viscoroute 2.0: a tool for the simulation of moving load effects on asphalt pavement

Modelisation de la reponse dynamique d'une structure ferroviaire multicouche sous chargement roulant

Effets des paramètres de conception des Lignes à Grande Vitesse sur les niveaux d'accélération dans le ballast