1、BS ISO 8608:2016 Mechanical vibration Road surface profiles Reporting of measured data BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 8608:2016 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 8608:2016. It supersedes
2、BS 7853:1996 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee GME/21/5, Mechanical vibration, shock and condition monitoring - Vibration of machines. A list of organizations represented on this committee can be obtained on request to its secretary. Thi
3、s publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 94289 1 ICS 17.160; 93.080.10 Compliance with a British Standard can
4、not confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2016. Amendments/Corrigenda issued since publication Date Text affectedBS ISO 8608:2016 ISO 2016 Mechanical vibration Road surface profile
5、s Reporting of measured data Vibrations mcaniques Profils de routes Mthode de prsentation des rsultats de mesures INTERNATIONAL STANDARD ISO 8608 Second edition 2016-11-01 Reference number ISO 8608:2016(E)BS ISO 8608:2016ISO 8608:2016(E)ii ISO 2016 All rights reserved COPYRIGHT PROTECTED DOCUMENT IS
6、O 2016, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permis
7、sion. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgBS ISO 8608:2016ISO
8、8608:2016(E)Foreword iv Introduction v 1 Scope . 1 2 Normative references 1 3 Terms and definitions . 1 4 Symbols 2 5 Uniform method of reporting 3 5.1 One-track data . 3 5.1.1 Description of the road profile. 3 5.1.2 Presentation of the smoothed power spectral density . 4 5.2 Multiple-track data 7
9、5.3 Report . 7 5.3.1 General 7 5.3.2 One-track data curve sheet . 7 5.3.3 Multiple-track data curve sheet 8 5.3.4 Parameters of analysis 8 5.3.5 Test conditions. 9 Annex A (informative) Example of a report 11 Annex B (informative) Road profile characterization and PSD fitting .17 Annex C (informativ
10、e) General guidance for use of the statistical road profile description.20 Annex D (informative) Considerations for PSD processing and precision .30 Bibliography .36 ISO 2016 All rights reserved iii Contents PageBS ISO 8608:2016ISO 8608:2016(E) Foreword ISO (the International Organization for Standa
11、rdization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right t
12、o be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures us
13、ed to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules
14、of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identifi
15、ed during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on
16、 the meaning of ISO specific terms and expressions related to conformit y assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html. The committee responsible
17、for this document is ISO/TC 108, Mechanical vibration, shock and condition monitoring, Subcommittee SC 2, Measurement and evaluation of mechanical vibration and shock as applied to machines, vehicles and structures. This second edition cancels and replaces the first edition (ISO 8608:1995), of which
18、 it constitutes a minor revision. The following changes have been made: normative references have been updated; subclause numbering has been adjusted; figures have been made language independent; bibliography has been updated; editorially revised.iv ISO 2016 All rights reservedBS ISO 8608:2016ISO 86
19、08:2016(E) Introduction The purpose of this document is to facilitate the compilation and comparison of measured vertical road profile data from various sources. It therefore specifies a uniform method of reporting data from one- track and multiple-track measurements. It specifies how measurements a
20、re to be reported, but not how the measurements are to be made. The measuring equipment can influence the results of the measurement; therefore certain characteristics of the measuring system have also to be reported. Annex A is an example of a report which meets the minimum requirements of this doc
21、ument. Annex B gives means of approximately characterizing specific road profiles in order to facilitate the division of road profiles into general classifications. A general classification is also given. A curve fitting method is presented for characterizing spectral data. Annex C provides general
22、guidance for the use of road profile statistical data for simulation studies and for related studies such as evaluation of comfort, suspensions and road profiles. Annex D discusses the processing of the power spectral density (PSD) with the fast Fourier transform (FFT) technique. A discussion on the
23、 statistical precision is also given. ISO 2016 All rights reserved vBS ISO 8608:2016BS ISO 8608:2016Mechanical vibration Road surface profiles Reporting of measured data 1 Scope This document specifies a uniform method of reporting measured vertical road profile data for either one-track or multiple
24、-track measurements. It applies to the reporting of measured vertical profile data taken on roads, streets and highways, and on off-road terrain. It does not apply to rail-track data. Measurement and processing equipment and methods are not included. 2 Normative references The following documents ar
25、e referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61260-1, Electroaco
26、ustics Octave-band and fractional-octave-band filters Part 1: Specifications 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 2041 and the following apply. ISO and IEC maintain terminological databases for use in standardization at the following addre
27、sses: IEC Electropedia: available at http:/ /www.electropedia.org/ ISO Online browsing platform: available at http:/ /www.iso.org/obp 3.1 spatial frequency reciprocal of the wavelength Note 1 to entry: The spatial frequency is expressed in cycles per metre (cycles/m). 3.2 power spectral density PSD
28、limiting mean-square value of a signal per unit frequency bandwidth Note 1 to entry: For a one-sided spectrum, the area located between the graphic plot and the horizontal axis in a linear plot should be equal to the variance 2of the original signal for the evaluated frequency range. This leads to a
29、 doubling of the spectral amplitude when the calculation process is only estimating the spectrum for positive frequencies. 3.3 displacement PSD power spectral density of the vertical road profile displacement 3.4 velocity PSD power spectral density of the rate of change of the vertical road profile
30、displacement per unit distance travelled (slope of the vertical road profile) INTERNATIONAL ST ANDARD ISO 8608:2016(E) ISO 2016 All rights reserved 1BS ISO 8608:2016ISO 8608:2016(E) 3.5 acceleration PSD power spectral density of the rate of change of the slope of the vertical road profile per unit d
31、istance travelled 3.6 decolouring procedure to eliminate the influence of the transfer function of the measuring system on the power spectral density Note 1 to entry: The raw power spectral density should be decoloured before any further processing by dividing it by the square of the modulus of the
32、measuring equipment transfer function. 3.7 smoothing averaging process in which a data block is shifted and averaged Note 1 to entry: In this document, “unsmoothed PSD” means the power spectral density as calculated from the measured data, i.e. with the bandwidths used in or following from the calcu
33、lations and which are different from those indicated in Table 2. The term “smoothed PSD” is the power spectral density which is obtained after using the averaging process described in 5.1.2. 4 Symbols The symbols used in this document are given in Table 1. Table 1 Symbols Symbol Description Unit B e
34、 Frequency resolution cycles/m f Time frequency Hz G d (.) Displacement PSD m 3 G v (.) Velocity PSD m G a (.) Acceleration PSD m 1 G 1 (.) PSD of track 1 G 2 (.) PSD of track 2 G 12 (.) Cross spectrum between tracks 1 and 2 l Wheelbase m n Spatial frequency cycles/m t Time s v Vehicle speed m/s 2 C
35、oherence function 2 Variance Angular frequency (= 2f ) rad/s Angular spatial frequency (= 2n) rad/m NOTE The indication (.) means that the parameter of the function can be spatial frequency (n) or angular spatial frequency ().2 ISO 2016 All rights reservedBS ISO 8608:2016ISO 8608:2016(E) 5 Uniform m
36、ethod of reporting 5.1 One-track data 5.1.1 Description of the road profile 5.1.1.1 General The road profile shall be described by one or both of the following methods, with preference for the first, the displacement PSD. The reporting of the non-smoothed data is always required. 5.1.1.2 First metho
37、d Displacement PSD: G d (.) The road profile shall be described by the power spectral density (PSD) of its vertical displacement. The report shall include the displacement PSD versus (angular) spatial frequency, both on logarithmic axes. The dimensions are metres cubed (m 3 ) versus reciprocal metre
38、s (cycles/m and rad/m). Two scales shall be given on the ordinate, one for G d (n) and one for G d (). Both n and scales shall be indicated in the abscissa. The grid, however, shall only be drawn for G d (n) and n (see Figure A.2, for example). 5.1.1.3 Second method Acceleration PSD: G a (.) The acc
39、eleration power spectral density (PSD) is an allowed alternative method of reporting data. In this case, the road profile shall be described as the PSD of its acceleration in terms of the rate of change of the slope of the road surface per unit distance travelled. The dimension of the acceleration P
40、SD is reciprocal metres (m 1 ). The scales shall be logarithmic on both axes. Two scales shall be given on the ordinate, one for G a (n) and one for G a (). On the abscissa, both n and shall be indicated. The grid, however, shall only be drawn for G a (n) and n. 5.1.1.4 Relationship between the two
41、reporting methods The relationship between the two reporting methods (see 5.1.1.2 and 5.1.1.3) is given by Formulae (1) and (2): G a (n) = (2n) 4 G d (n) (1) G a () = 4 G d () (2) 5.1.1.5 Spatial frequency range The reported PSD shall be restricted between the limits allowed by the measuring equipme
42、nt. For the report, the user may select any spatial frequency range appropriate to his/her particular road surface, problem and product. The measured surface depends on the measuring equipment, which has a certain smoothing effect. This equipment is to be reported (see Note 4 and 5.3.5.2.1). NOTE 1
43、Figure C.1 gives the relationship between the vehicle speed, the spatial frequency and the time frequency. Knowledge of the frequency and speed characteristics for a given class of vehicles makes it possible to choose the useful limits for that class of vehicle (e.g. on-road or off-road vehicles). I
44、SO 2016 All rights reserved 3BS ISO 8608:2016ISO 8608:2016(E) NOTE 2 For the lower limit, the spatial frequency need not in general be measured lower than 0,01 cycles/m for on-road vehicles and 0,05 cycles/m for off-road vehicles. NOTE 3 The enveloping effect of the tyre acts as a low-pass filter fo
45、r the road vibration input to the vehicle. This effect depends on the size and construction of the tyre. For general on-road measurements, this results in a recommended upper limit of 10 cycles/m. Of course for suspension vibration purposes, the interesting upper limit depends on the maximum allowed
46、 speed on the particular road. For noise purposes, the interesting upper limit may be much higher, and may go as high as 1 000 cycles/m. NOTE 4 Due to the tyre width there is also an enveloping effect in the lateral direction. This means that for vibration purposes, the mean of the footprint is usua
47、lly measured. The width depends on the problem (e.g. vibration, noise) and the product (e.g. motorcycle tyres, truck tyres). For general on-road measurements not intended for a specific product, a track of about 100 mm wide is often used for vibration purposes. For noise purposes, a point measuremen
48、t is often used. NOTE 5 For off-road measurements, care needs to be taken when interpreting the high frequencies. For soft (e.g. sandy) surfaces, short undulations could be flattened by the wheel load and filtered out. For hard (e.g. stone) surfaces, however, only the enveloping effect of the tyre a
49、cts as a filter. In this situation, the surface needs to be described accurately in the data sheet (see 5.3.5.3.2). NOTE 6 Annex B gives recommended methods for the characterization of the road profile and for the fitting of the measured data. 5.1.2 Presentation of the smoothed power spectral density When the power spectral densities are calculated with a constant bandwidth method, their representation in a log-log diagram give an appearance or visual impression at high frequen
