Uncertainty in the standardized method "Characterization of the acoustic properties of road surfaces" by CEN TC227 WG5

2021 ◽  
Vol 263 (6) ◽  
pp. 314-322
Author(s):  
Gijsjan van Blokland ◽  
Luc Goubert

TC227 of CEN has developed a method to determine the effect of the road pavement on the sound emission of road vehicles. The proposed methods can be applied to define the acoustic label value of a generic or proprietary pavement type, to check compliance of a pavement with the specifications for that pavement type and to monitor the development of the acoustic properties over the lifetime of the product. With the procedure one can additionally derive the coefficients for the pavement correc tion in the noise emission formulae for road vehicles in the CNOSSOS-EU calculation model. The application of the method exhibits a limited accuracy. The paper investigates the sources of uncertainty of the standardized method and combine the contributions into a single overall uncertainty according to the procedures laid down in Guide 98-3 of ISO. The uncertainty is determined for each of the listed application areas. From the uncertainty analysis the major contributions are identified. Improvement of the method shall focus on only these contributions.

2015 ◽  
Vol 61 (4) ◽  
pp. 107-126 ◽  
Author(s):  
K. J. Kowalski ◽  
A. J. Brzeziński ◽  
J. B. Król ◽  
P. Radziszewski ◽  
Ł. Szymański

Traffic related noise is currently considered as an environmental pollution. Paper presents results of multidirectional study attempting to serve urban traffic without the need to erect noise barriers interfering urban space. Initial concept of the road expansion included construction of 1000 m of noise barriers dividing city space. Improvement in the acoustic conditions after construction completion is possible due to the applied noise protection measures: vehicle speed limit, smooth of traffic flow, use of road pavement of reduced noise emission and the technical improvement of the tramway.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Johannes Masino ◽  
Jakob Thumm ◽  
Guillaume Levasseur ◽  
Michael Frey ◽  
Frank Gauterin ◽  
...  

This work aims at classifying the road condition with data mining methods using simple acceleration sensors and gyroscopes installed in vehicles. Two classifiers are developed with a support vector machine (SVM) to distinguish between different types of road surfaces, such as asphalt and concrete, and obstacles, such as potholes or railway crossings. From the sensor signals, frequency-based features are extracted, evaluated automatically with MANOVA. The selected features and their meaning to predict the classes are discussed. The best features are used for designing the classifiers. Finally, the methods, which are developed and applied in this work, are implemented in a Matlab toolbox with a graphical user interface. The toolbox visualizes the classification results on maps, thus enabling manual verification of the results. The accuracy of the cross-validation of classifying obstacles yields 81.0% on average and of classifying road material 96.1% on average. The results are discussed on a comprehensive exemplary data set.


2017 ◽  
Vol 90 (2) ◽  
pp. 405-427 ◽  
Author(s):  
Mehran Motamedi ◽  
Saied Taheri ◽  
Corina Sandu ◽  
Pierrick Legrand

ABSTRACT A major challenge in tire and road engineering is to understand the intricate mechanisms of friction. Pavement texture is a feature of the road surface that determines most tire–road interactions, and it can be grouped into two classes of macro-texture and micro-texture. Since the effects of micro-texture and macro-texture dominate the friction measurements at low and high slip speeds, they can help provide sufficient resistance to skidding, if maintained at high levels. A non-contact profilometer is used to measure the macro- and micro-texture of several different road surfaces. The friction number for each surface is measured using the Michigan Department of Transportation's (MDOT) single axle friction trailer. Some fractal parameters of the measured profiles are estimated, and it is proved that all measured profiles display strong fractal behavior. The correlation between texture and fractal parameters and friction is investigated. It is shown that while global fractal quantities fail to classify pavement profiles, the pointwise Hölder exponent as a local fractal parameter, and also the mean square roughness, can discriminate profiles that have different frictional properties. For five road surfaces, two-dimensional (2D) characterization is done using one-dimensional (1D) profile measurements. The hysteretic coefficient of friction is estimated using the contact theory developed by B.N.J. Persson. Good correlation is observed between the wet friction measurements and friction prediction results.


2016 ◽  
Vol 105 ◽  
pp. 93-98 ◽  
Author(s):  
David Ibarra ◽  
Ricardo Ramírez-Mendoza ◽  
Saúl Ibarra
Keyword(s):  
The Road ◽  

1968 ◽  
Vol 41 (4) ◽  
pp. 832-842 ◽  
Author(s):  
E. M. Bevilacqua ◽  
E. P. Percarpio

Abstract This review introduces a series of reports on a quantitative study of friction of rubber on wet surfaces. It was derived from concern over safety aspects of skidding on wet roads; this first paper deals with the relation between safety and traction. Subsequent papers deal with: A quantitative approach to characterization of road surfaces, identification of the surface features of importance, and estimation of their relative contributions to lubricated friction. Quantitative estimates of effects of properties of rubber materials on lubricated friction and an analysis of their relative importance in interaction with the significant features of the road surface. A quantitative basis for evaluation of wet skid resistance of roads, the choice of the rubber to be used in this evaluation, and methods of testing. An improved technique to measure the property of tread rubber important for wet skid resistance of tires. Identification and interpretation of the nature of friction on ice at low temperatures.


2018 ◽  
Vol 97 (12) ◽  
pp. 1171-1178 ◽  
Author(s):  
Yu. A. Rakhmanin ◽  
A. V. Levanchuk ◽  
Olga I. Kopytenkova ◽  
N. M. Frolova ◽  
A. M. Sazonova

Introduction. According to the materials of the World Health Organization, air pollutants are one of the most significant factors affecting the health of the population. The main urban air pollution source is road transport. The determination of air pollutants amount during the operation of the road-vehicles complex (RVC) with suspended substances is an important procedure for monitoring the risk to human health, planning, and evaluation of measures for the protection of residential areas ambient air. The existing methodical documents and regulations do not fully regulate important aspects of air pollution monitoring and assessment by-products caused by exhaust gases of the vehicle and emissions associated with the operation of the RVC. Thus, the purpose of this study is to determine the additional population health risks due to pollutants reaching the air of residential areas during the RVC operation. Material and methods. The method of emissions measurement reaching the air during the operation of the RVC is based on existing methodical documents and regulations. To assess the pollution, the data of observations of the intensity of traffic flow in different time periods in the experimental territories are used. The calculation of pollutants amount released into the air during the operational wear of the RVC is determined separately for the tire treads, brake system, and road pavement. Results. Guided by the constructed nomogram, taking into account distribution zone of the air pollution, it is possible to determine population health risk during the RVC operation in the city based on the calculation of the hazard coefficient. Discussion. On the basis of the calculations, data on the number of pollutants reaching the air during the RVC operation (wear of tire treads, brake system, road pavement) and from vehicles of various types for 1 year are presented. The data on the pollutants quantities generating on the road on a per 1 km car run basis, reaching the ambient air for various periods of time (hours, days) with the aim of the derivation of the spatial-temporal characteristics of the pollutants. On the basis of the obtained data, approximate calculations of the number of pollutants reaching the air during the operation of the RVC from all vehicles registered by St. Petersburg traffic police at the moment and the forecast for the period 2020 were carried out. Сonclusions. The given data on the hazard coefficient calculation of suspended solids emissions of RVC allow summarizing the risk from all the compartmental RVC sources. On the basis of the distance from the road to residential buildings presented in the nomogram, it is possible to determine an additional population health risk due to pollutants reaching the air during the RVC operation using a mathematical model of dispersion.


Author(s):  
D Cebon

Theory is presented for simulating the dynamic wheel forces generated by heavy road vehicles and the resulting dynamic response of road surfaces to these loads. Sample calculations are provided and the vehicle simulation is validated with data from full-scale tests. The methods are used in the accompanying paper to simulate the road damage done by a tandem-axle vehicle.


Noise Mapping ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 217-227
Author(s):  
Julien Cesbron ◽  
Simon Bianchetti ◽  
Marie-Agnès Pallas ◽  
Adrien Le Bellec ◽  
Vincent Gary ◽  
...  

Abstract Considering the relative quietness of electric motors, tyre/road interaction has become the prominent source of noise emission from Electric Vehicles (EVs). This study deals with the potential influence of the road surface on EV noise emission, especially in urban area. A pass-by noise measurement campaign has been carried out on a reference test track, involving six different road surfaces and five electric passenger car models in different vehicle segments. The immunity of sound recordings to background noise was considered with care. The overall and spectral pass-by noise levels have been analysed as a function of the vehicle speed for each couple of road surface and EV model. It was found that the type of EV has few influence on the noise classification of the road surfaces at 50 km/h. However, the noise level difference between the quietest and the loudest road surface depends on the EV model, with an average close to 6 dBA, showing the potential effect of the road surface on noise reduction in the context of growing EV fleet in urban area. The perspective based on an average passenger EV in a future French or European electric fleet is addressed.


2008 ◽  
Vol 75 (6) ◽  
Author(s):  
Simos Evangelou ◽  
David J. N. Limebeer ◽  
Maria Tomas Rodriguez

This paper studies the influence of road camber on the stability of single-track road vehicles. Road camber changes the magnitude and direction of the tire force and moment vectors relative to the wheels, as well as the combined-force limit one might obtain from the road tires. Camber-induced changes in the tire force and moment systems have knock-on consequences for the vehicle’s stability. The study makes use of computer simulations that exploit a high-fidelity motorcycle model whose parameter set is based on a Suzuki GSX-R1000 sports machine. In order to study camber-induced stability trends for a range of machine speeds and roll angles, we study the machine dynamics as the vehicle travels over the surface of a right circular cone. Conical road surfaces allow the machine to operate at a constant steady-state speed, a constant roll angle, and a constant road camber angle. The local road-tire contact behavior is analyzed by approximating the cone surface by moving tangent planes located under the road wheels. There is novelty in the way in which adaptive controllers are used to center the vehicle’s trajectory on a cone, which has its apex at the origin of the inertial reference frame. The results show that at low speed both the weave- and wobble-mode stabilities are at a maximum when the machine is perpendicular to the road surface. This trend is reversed at high speed, since the weave- and wobble-mode dampings are minimized by running conditions in which the wheels are orthogonal to the road. As a result, positive camber, which is often introduced by road builders to aid drainage and enhance the friction limit of four-wheeled vehicle tires, might be detrimental to the stability of two-wheeled machines.


Author(s):  
B. Behzodi ◽  
K. A. Andrianov ◽  
A. F. Zubkov

The remoteness of the construction site from the production base, large volumes of work, insufficient productivity of asphalt concrete plants for the preparation of hot asphalt concrete mixtures makes urgent the use of cold bitumen concrete mixes for the road construction. The preliminary mix preparation on the production sites with preservation of its properties for several months allows to increase the duration of the construction season. Purpose. Quality improvement of construction of non-rigid road surfaces using cold bitumen concrete mixes. Materials and methods. Models of road pavement structure based on cold bitumen concrete mixes are proposed to clarify the influence of the structural, climatic, technological and thermophysical properties of materials on the pavement quality. Research results. It is shown that the construction of road surfaces using cold bitumen concrete mixes even at positive ambient temperatures, does not provide the required surface quality. Conclusions. To improve the road paving quality using cold bitumen concrete mixes is necessary to heat the base before laying the cold mix. The heating temperature of the base depends on the layer thickness and ambient temperature.


Sign in / Sign up

Export Citation Format

Share Document