BS EN 1793-5-2016 Road traffic noise reducing devices Test method for determining the acoustic performance Intrinsic characteristics In situ values of sound reflection under direct.pdf

1、BSI Standards PublicationBS EN 1793-5:2016Road traffic noise reducing devices Test method for determining the acoustic performancePart 5: Intrinsic characteristics In situ values of sound reflection under direct sound field conditionsBS EN 1793-5:2016 BRITISH STANDARDNational forewordThis British St

2、andard is the UK implementation of EN 1793-5:2016. It supersedes BS CEN/TS 1793-5:2003 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee B/509/6, Fences for the attenuation of noise.A list of organizations represented on this committee can be obtained on

3、 request to its secretary.This 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 2016ISBN 978 0 580 85653 2 ICS 17.140.30; 93.080.30 Complia

4、nce with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2016.Amendments/corrigenda issued since publicationDate Text affectedBS EN 1793-5:2016EUROPEAN STANDARD NORME E

5、UROPENNE EUROPISCHE NORM EN 1793-5 March 2016 ICS 17.140.30; 93.080.30 Supersedes CEN/TS 1793-5:2003English Version Road traffic noise reducing devices - Test method for determining the acoustic performance - Part 5: Intrinsic characteristics - In situ values of sound reflection under direct sound f

6、ield conditions Dispositifs de rduction du bruit du trafic routier - Mthode dessai pour la dtermination de la performance acoustique - Partie 5: Caractristiques intrinsques - Valeurs in situ de rflexion acoustique dans des conditions de champ acoustique direct Lrmschutzvorrichtungen an Straen - Prfv

7、erfahren zur Bestimmung der akustischen Eigenschaften - Teil 5: Produktspezifische Merkmale - In-situ-Werte der Schallreflexion in gerichteten Schallfeldern This European Standard was approved by CEN on 23 January 2016. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which

8、stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This Europ

9、ean Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are

10、 the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Rom

11、ania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and b

12、y any means reserved worldwide for CEN national Members. Ref. No. EN 1793-5:2016 EBS EN 1793-5:2016EN 1793-5:2016 (E) 2 Contents European foreword 4 Introduction . 6 1 Scope . 8 2 Normative references . 8 3 Terms and definitions 8 4 Symbols and abbreviations . 13 5 Sound reflection index measurement

13、s . 15 5.1 General principle . 15 5.2 Measured quantity 15 5.3 Test arrangement 18 5.4 Measuring equipment . 23 5.4.1 Components of the measuring system . 23 5.4.2 Sound source . 24 5.4.3 Test signal 24 5.5 Data processing 25 5.5.1 Calibration . 25 5.5.2 Sample rate 26 5.5.3 Background noise . 27 5.

14、5.4 Signal subtraction technique 27 5.5.5 Adrienne temporal window 30 5.5.6 Placement of the Adrienne temporal window 32 5.5.7 Low frequency limit and sample size . 33 5.6 Positioning of the measuring equipment . 35 5.6.1 Maximum sampled area 35 5.6.2 Selection of the measurement positions. 35 5.6.3

15、 Reflecting objects 42 5.6.4 Safety considerations. 42 5.7 Sample surface and meteorological conditions . 42 5.7.1 Condition of the sample surface 42 5.7.2 Wind . 42 5.7.3 Air temperature . 42 5.8 Single-number rating of sound reflection DLRI. 42 5.9 Measurement uncertainty . 43 5.10 Measuring proce

16、dure 43 5.11 Test report . 44 Annex A (informative) Measurement uncertainty 46 A.1 General 46 A.2 Measurement uncertainty based upon reproducibility data 46 A.3 Standard deviation of repeatability and reproducibility of the sound reflection index . 46 Annex B (informative) Template of test report on

17、 sound reflection of road noise barriers . 48 B.1 Overview 48 B.2 Test setup (example) . 50 B.3 Test object and test situation (example) 51 BS EN 1793-5:2016EN 1793-5:2016 (E) 3 B.4 Test Results (example) 53 B.4.1 Part 1 Results in tabular form 53 B.4.2 Part 2 Results in graphic form 54 B.5 Uncertai

18、nty (example) . 54 Annex C (informative) Near field to far field relationship 56 Bibliography . 57 BS EN 1793-5:2016EN 1793-5:2016 (E) 4 European foreword This document (EN 1793-5:2016) has been prepared under the direction of Technical Committee CEN/TC 226 “Road equipment”, by Working Group 6 “Anti

19、-noise devices”, the secretariat of which is held by AFNOR. This document supersedes CEN/TS 1793-5:2003. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2016, and conflicting national st

20、andards shall be withdrawn at the latest by September 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. With respect to the supers

21、eded document, the following changes have been done: the rotating loudspeaker/microphone assembly has been replaced by a loudspeaker and a 9-microphone square array (the measurement grid); the definition of RI has been changed; the geometrical divergence correction factor has been changed; a new cor

22、rection factor for sound source directivity has been introduced; a new correction factor for gain mismatch has been introduced; the impulse response alignment for signal subtraction has been described in more detail; the lowest reliable one-third frequency band has been better defined; the way to ev

23、aluate the uncertainty of the measurement method from reproducibility data has been introduced (Annex A); a detailed example is given (Annex B); information on the near-field to far-field relationship has been added (Annex C). It should be read in conjunction with: EN 1793-1, Road traffic noise redu

24、cing devices - Test method for determining the acoustic performance Part 1: Intrinsic characteristics of sound absorption under diffuse sound field conditions EN 1793-2, Road traffic noise reducing devices - Test method for determining the acoustic performance Part 2: Intrinsic characteristics of ai

25、rborne sound insulation under diffuse sound field conditions EN 1793-3, Road traffic noise reducing devices - Test method for determining the acoustic performance Part 3: Normalized traffic noise spectrum EN 1793-4, Road traffic noise reducing devices - Test method for determining the acoustic perfo

26、rmance Part 4: Intrinsic characteristics In situ values of sound diffraction EN 1793-6, Road traffic noise reducing devices - Test method for determining the acoustic performance Part 6: Intrinsic characteristics In situ values of airborne sound insulation under direct sound field conditions BS EN 1

27、793-5:2016EN 1793-5:2016 (E) 5 According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Rep

28、ublic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 1793-5:2016EN 1793-5:2016 (E) 6 Introduction This

29、document describes a test method for determining the intrinsic characteristics of sound reflection of noise reducing devices designed for roads in non-reverberant conditions (a measure of intrinsic performance). It can be applied in situ, i.e. where the noise reducing devices are installed. The meth

30、od can be applied without damaging the surface. The method can be used to qualify products to be installed along roads as well as to verify the compliance of installed noise reducing devices to design specifications. Regular application of the method can be used to verify the long term performance o

31、f noise reducing devices. The method requires the average of results of measurements taken in different points in front of the device under test and/or for specific angles of incidences. The method is able to investigate flat and non-flat products. The measurements results of this method for sound r

32、eflection are not directly comparable with the results of the laboratory method (e.g. EN 1793-1), mainly because the present method uses a directional sound field, while the laboratory method assumes a diffuse sound field. The test method described in the present document should not be used to deter

33、mine the intrinsic characteristics of sound reflection of noise reducing devices to be installed in reverberant conditions, e.g. claddings inside tunnels or deep trenches. For the purpose of this document reverberant conditions are defined based on the envelope, e, across the road formed by the devi

34、ce under test, trench sides or buildings (the envelope does not include the road surface) as shown by the dashed lines in Figure 1. Conditions are defined as being reverberant when the percentage of open space in the envelope is less than or equal to 25 %, i.e. Reverberant conditions occur when w/e

35、0,25, where e = (w+h1+h2) This method introduces a specific quantity, called reflection index, to define the sound reflection in front of a noise reducing device, while the laboratory method gives a sound absorption coefficient. Laboratory values of the sound absorption coefficient can be converted

36、to conventional values of a reflection coefficient taking the complement to one. In this case, research studies suggest that some correlation exists between laboratory data, measured according to EN 1793-1 and field data, measured according to the method described in the present document 7, 10, 20,

37、21. This method may be used to qualify noise reducing devices for other applications, e.g. to be installed nearby industrial sites. In this case the single-number ratings should be calculated using an appropriate spectrum. BS EN 1793-5:2016EN 1793-5:2016 (E) 7 (a) Partial cover on both sides of the

38、road; envelope, e = w+h1+h2. (b) Partial cover on one side of the road; envelope, e = w+h1. (c) Deep trench; envelope, e = w+h1+h2. (d) Tall barriers or buildings; envelope, e = w+h1+h2. Key r road surface; w width of open space NOTE Figure 1 is not to scale. Figure 1 Sketch of the reverberant condi

39、tion check in four cases BS EN 1793-5:2016EN 1793-5:2016 (E) 8 1 Scope This European Standard describes a test method for measuring a quantity representative of the intrinsic characteristics of sound reflection from road noise reducing devices: the reflection index. The test method is intended for t

40、he following applications: determination of the intrinsic characteristics of sound reflection of noise reducing devices to be installed along roads, to be measured either on typical installations alongside roads or on a relevant sample section; determination of the in situ intrinsic characteristics

41、of sound reflection of noise reducing devices in actual use; comparison of design specifications with actual performance data after the completion of the construction work; verification of the long term performance of noise reducing devices (with a repeated application of the method). The test metho

42、d is not intended for the following applications: determination of the intrinsic characteristics of sound reflection of noise reducing devices to be installed in reverberant conditions, e.g. inside tunnels or deep trenches. Results are expressed as a function of frequency, in one-third octave bands

43、between 100 Hz and 5 kHz. If it is not possible to get valid measurements results over the whole frequency range indicated, the results should be given in a restricted frequency range and the reasons of the restriction(s) should be clearly reported. 2 Normative references The following documents, in

44、 whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1793-3, Road traffic noise redu

45、cing devices - Test method for determining the acoustic performance - Part 3: Normalized traffic noise spectrum EN 61672-1, Electroacoustics Sound level meters Part 1: Specifications (IEC 61672-1) ISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measur

46、ement (GUM:1995) 3 Terms and definitions For the purposes of this document the following terms and definitions apply: 3.1 noise reducing device (NRD) device that is designed to reduce the propagation of traffic noise away from the road environment. This may be a noise barrier, cladding, a road cover

47、 or an added device. These devices may include both acoustic and structural elements BS EN 1793-5:2016EN 1793-5:2016 (E) 9 3.2 noise barrier noise reducing device, which obstructs the direct transmission of airborne sound emanating from road traffic 3.3 acoustic element element whose primary functio

48、n is to provide the acoustic performance of the device 3.4 structural element element whose primary function is to support or hold in place acoustic elements 3.5 cladding noise-reducing device, which is attached to a wall or other structure and reduces the amount of sound reflected 3.6 cover noise-r

49、educing device, which either spans or overhangs the highway 3.7 added device added component that influences the acoustic performance of the original noise-reducing device (acting primarily on the diffracted energy) 3.8 roadside exposure the use of the product as a noise reducing device installed alongside roads 3.9 sound reflection index quantity, resulting from a sound reflection test, described by Formula (1) 3.10 measurement grid for sound reflection index measurements vertical measurement grid con