BS EN 15610:2009

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 Measuring system requirements
   5.1 General
   5.2 Accuracy of the output signal
   5.3 Dimensions of the probe
   5.4 Tracking of the probe
   5.5 Sampling interval
   5.6 Record length
6 Data acquisition
   6.1 General
   6.2 Test section requirements
   6.2.1 Track structure
   6.2.2 Localized geometric features
   6.3 Reference surface choice
   6.4 Data sampling
       6.4.1 General
       6.4.2 Longitudinal sampling
       6.4.3 Lateral sampling
   6.5 Preparation of the rail head surface
   6.6 Acoustic roughness acquisition
7 Data processing
   7.1 Principle
   7.2 Spike removal technique
   7.3 Curvature processing
   7.4 Spectral analysis
       7.4.1 Method A: Fourier analysis
       7.4.2 Method B: digital filtering
   7.5 Procedure for extending the wavelength range
   7.6 Averaging process
8 Acceptance criteria
9 Presentation of the data
10 Report
Annex A (informative) - Examples of rail defects
Annex B (informative) - Example of program code to
        implement acoustic roughness processing
      B.1 Purpose
      B.2 Conditions of use
      B.3 List of Matlab program files
      B.4 Input data file requirements
      B.5 Processing options
      B.6 Spectral analysis
      B.7 1/3 octave reporting
      B.8 Output
      B.9 Listing
          B.9.1 file RoughProcess.m
          B.9.2 21
          B.9.3 file ruw_curve_rp.m
          B.9.4 file noct_rp.m
Annex C (normative) - Algorithm used to synthesize a
        one-third octave band spectrum from a
        corresponding narrow band spectrum
Annex ZA (informative) - Relationship between this European
         Standard and the Essential Requirements of EU
         Directive EU 2008/57/EC
Bibliography

Describes a direct method for characterizing the surface roughness of the rail associated with rolling noise ("acoustic roughness"), in the form of a one-third octave band spectrum.

1.1 This European Standard specifies a direct method for characterizing the surface roughness of the rail associated with rolling noise (\'acoustic roughness\'), in the form of a one-third octave band spectrum. This standard describes a method for: a) selecting measuring positions; b) data acquisition; c) measurement data processing in order to estimate a set of one-third octave band roughness spectra; d) presentation of this estimate for comparison with limits of acoustic roughness; e) comparison with a given upper limit in terms of a one-third octave band wavelength spectrum. 1.2 It is applicable to the: a) performance testing of reference track sections for the measurement, within a period of three months before or after roughness characterization, of noise emitted by railway vehicles for acceptance testing purposes; b) acceptance of the rail surface condition only in the case where the result of the direct measurement of the acoustic roughness is regarded as an established acceptance criterion. 1.3 It is not applicable to the: a) measurement of rail roughness using an indirect method; b) measurement of combined wheel-rail roughness; c) analysis of the effect of wheel-rail interaction, such as a “contact filter??; d) approval of rail reprofiling, including rail grinding operations, except for those where the acoustic roughness (and not the level of corrugation) is an established approval criterion; e) characterization of track geometry. Testing and approval of measuring apparatus are not part of the scope of this standard.