SIST EN ISO 13473-5:2010

SLOVENSKI STANDARD
SIST EN ISO 13473-5:2010
01-junij-2010
.DUDNWHUL]DFLMDWHNVWXUHYR]LãþD]XSRUDERSURILORYSRYUãLQHGHO8JRWDYOMDQMH
PHJDWHNVWXUH,62
Characterization of pavement texture by use of surface profiles - Part 5: Determination of
megatexture (ISO 13473-5:2009)
Charakterisierung der Textur von Fahrbahnbelägen unter Verwendung von
Oberflächenprofilen - Teil 5: Bestimmung der Megatextur (ISO 13473-5:2009)
Caractérisation de la texture d'un revêtement de chaussée à partir de relevés de profils
de la surface - Partie 5: Détermination de la mégatexture (ISO 13473-5:2009)
Ta slovenski standard je istoveten z: EN ISO 13473-5:2009
ICS:
17.140.30 Emisija hrupa transportnih Noise emitted by means of
sredstev transport
93.080.20 Materiali za gradnjo cest Road construction materials
SIST EN ISO 13473-5:2010 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN ISO 13473-5:2010

---------------------- Page: 2 ----------------------

SIST EN ISO 13473-5:2010


EUROPEAN STANDARD
EN ISO 13473-5

NORME EUROPÉENNE

EUROPÄISCHE NORM
December 2009
ICS 17.140.30; 93.080.20
English Version
Characterization of pavement texture by use of surface profiles -
Part 5: Determination of megatexture (ISO 13473-5:2009)
Caractérisation de la texture d'un revêtement de chaussée Charakterisierung der Textur von Fahrbahnbelägen unter
à partir de relevés de profils de la surface - Partie 5: Verwendung von Oberflächenprofilen - Teil 5: Bestimmung
Détermination de la mégatexture (ISO 13473-5:2009) der Megatextur (ISO 13473-5:2009)
This European Standard was approved by CEN on 1 December 2009.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which 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 Management Centre or to any CEN member.

This European 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 Management Centre has the same status as the
official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.






EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13473-5:2009: E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------

SIST EN ISO 13473-5:2010
EN ISO 13473-5:2009 (E)
Contents Page
Foreword .3

2

---------------------- Page: 4 ----------------------

SIST EN ISO 13473-5:2010
EN ISO 13473-5:2009 (E)
Foreword
The text of ISO 13473-5:2009 has been prepared by Technical Committee ISO/TC 43 “Acoustics” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 13473-5:2009 by
Technical Committee CEN/TC 227 “Road materials” the secretariat of which is held by DIN.
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 June 2010, and conflicting national standards shall be withdrawn at
the latest by June 2010.
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.
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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 13473-5:2009 has been approved by CEN as a EN ISO 13473-5:2009 without any
modification.

3

---------------------- Page: 5 ----------------------

SIST EN ISO 13473-5:2010

---------------------- Page: 6 ----------------------

SIST EN ISO 13473-5:2010

INTERNATIONAL ISO
STANDARD 13473-5
First edition
2009-03-15


Characterization of pavement texture by
use of surface profiles —
Part 5:
Determination of megatexture
Caractérisation de la texture d'un revêtement de chaussée à partir de
relevés de profils de la surface —
Partie 5: Détermination de la mégatexture





Reference number
ISO 13473-5:2009(E)
©
ISO 2009

---------------------- Page: 7 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.


COPYRIGHT PROTECTED DOCUMENT


©  ISO 2009
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland

ii © ISO 2009 – All rights reserved

---------------------- Page: 8 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
4 Significance and use of the megatexture indicators . 6
5 Measurement and data processing principles . 8
6 Test surface considerations . 9
7 Measuring equipment. 9
8 Measurement method. 10
9 Data processing. 12
10 Measurement uncertainty . 15
11 Safety considerations during measurements. 15
12 Test report . 16
Annex A (informative) Example of test report and graphical presentations. 18
Annex B (informative) Measurement uncertainty . 24
Annex C (informative) Profile asymmetry issues. 27
Bibliography . 29

© ISO 2009 – All rights reserved iii

---------------------- Page: 9 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
Foreword
ISO (the International Organization for Standardization) 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 to 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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 13473-5 was prepared by Technical Committee ISO/TC 43, Acoustics, Subcommittee SC 1, Noise.
ISO 13473 consists of the following parts, under the general title Characterization of pavement texture by use
of surface profiles:
⎯ Part 1: Determination of Mean Profile Depth
⎯ Part 2: Terminology and basic requirements related to pavement texture profile analysis
⎯ Part 3: Specification and classification of profilometers
⎯ Part 4: Spectral analysis of surface profiles [Technical Specification]
⎯ Part 5: Determination of megatexture
iv © ISO 2009 – All rights reserved

---------------------- Page: 10 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
Introduction
Pavement surface texture largely influences factors such as noise emission caused by tyre/road interaction
(Reference [7]), tyre/pavement friction (Reference [8]), and comfort, as well as rolling resistance and wear of
tyres. Reliable methods of texture measurement are therefore essential.
Texture is subdivided into micro-, macro- and megatexture according to ISO 13473-2. A method for
measurement and calculation of a macrotexture indicator based on a profile measurement is specified in
ISO 13473-1. A procedure for measuring macrotexture by the volumetric patch method is described in
[2]
ISO 10844:1994 , Annex A. Currently, no reliable and practical method of measuring pavement microtexture
in situ is available. This part of ISO 13473 aims to provide means of measuring and calculating megatexture
indicators useful for pavement surface characterization.
Megatexture is an important texture range lying between macrotexture and unevenness. This type of texture
has wavelengths of the same order of magnitude as a tyre/road interface and is often a result of potholes or
'washboarding'. Some common types of singularities, such as a single depressed or protruding spot on the
pavement, will also show up in a texture profile spectrum as megatexture. Although some pavements, such as
paving stones, possess an intrinsic megatexture, it is usually an unwanted characteristic resulting from defects
in the surface.
The scope of ISO 13473 (all parts) does not include profile analysis of road unevenness, which is dealt with in
[1]
ISO 8608 .

© ISO 2009 – All rights reserved v

---------------------- Page: 11 ----------------------

SIST EN ISO 13473-5:2010

---------------------- Page: 12 ----------------------

SIST EN ISO 13473-5:2010
INTERNATIONAL STANDARD ISO 13473-5:2009(E)

Characterization of pavement texture by use of surface
profiles —
Part 5:
Determination of megatexture
1 Scope
This part of ISO 13473 specifies procedures for determining the average depth or level of pavement surface
megatexture by measuring the profile curve of a surface and calculating megatexture descriptors from this
profile. The technique is designed to give meaningful and accurate measurements and descriptions of
pavement megatexture characteristics for various purposes.
Since there is an overlap between megatexture and the surrounding ranges, the megatexture descriptors
unavoidably have a certain correlation with corresponding measures in those ranges. This part of ISO 13473
specifies measurements and procedures which are in relevant parts compatible with those in ISO 13473-1,
[1] [6]
ISO 8608 and EN 13036-5 .
2 Normative references
The following referenced documents are indispensable for the application 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.
ISO 13473-2:2002, Characterization of pavement texture by use of surface profiles — Part 2: Terminology and
basic requirements related to pavement texture profile analysis
ISO 13473-3:2002, Characterization of pavement texture by use of surface profiles — Part 3: Specification
and classification of profilometers
ISO/TS 13473-4:2008, Characterization of pavement texture by use of surface profiles — Part 4: Spectral
analysis of surface profiles
ISO/IEC NP Guide 98-3:2008, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty
in measurement (GUM:1995)
IEC 61260, Electroacoustics — Octave-band and fractional-octave-band filters
3 Terms and definitions
For the purposes of this part of ISO 13473, the terms and definitions in ISO 13473-2, especially the following,
apply.
© ISO 2009 – All rights reserved 1

---------------------- Page: 13 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
3.1 General terms
3.1.1
pavement texture
texture
deviation of a pavement surface from a true planar surface, with a texture wavelength less than 0,5 m
NOTE It is divided into micro-, macro- and megatexture according to 3.2.
[ISO 13473-2:2002]
3.1.2
surface profile
texture profile
two-dimensional sample of the pavement surface generated if a sensor, such as the tip of a needle or a laser
spot, continuously touches or shines on the pavement surface while it is moved along a line on the surface
NOTE 1 The profile of the surface is described by two coordinates: one in the surface plane, called “distance” (the
abscissa), and the other in a direction normal to the surface plane, called “vertical displacement” (the ordinate). An
example is illustrated in Figure 1. The distance may be in the longitudinal or lateral (transverse) directions in relation to the
travel direction on a pavement, or any direction between these.
NOTE 2 Adapted from ISO 13473-2:2002.
NOTE 3 Texture profile is similar to surface profile but limited to the texture range.
NOTE 4 “Texture wavelength” is a descriptor of the wavelength components of the profile and is related to the concept
of the Fourier transform of a time series. However, mathematically the correspondence is not exact. Note that vertical
displacement (height) has an arbitrary reference.

Key
1 vertical displacement
2 profile
3 texture wavelength
4 distance
Figure 1 — Illustration of some basic terms describing pavement surface texture
3.1.3
profilometer
device used for measuring the profile of pavement surface
NOTE 1 Current designs of profilometers used in pavement engineering include, but are not limited to, sensors based
on laser, light sectioning, needle tracer and ultrasonics technologies.
[ISO 13473-2:2002]
NOTE 2 Specifications for profilometers are dealt with in ISO 13473-3.
2 © ISO 2009 – All rights reserved

---------------------- Page: 14 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
3.2 Ranges of texture
3.2.1
microtexture
pavement microtexture
deviation of a pavement surface from a true planar surface with the characteristic dimensions along the
surface of less than 0,5 mm, corresponding to texture wavelengths up to 0,5 mm expressed as one-third-
octave centre wavelengths
NOTE 1 Peak-to-peak amplitudes normally vary in the range 0,001 mm to 0,5 mm. This type of texture is the texture
which makes the surface feel more or less harsh but which is usually too small to be observed by the eye. It is produced
by the surface properties (sharpness and harshness) of the individual chippings or other particles of the surface which
come in direct contact with the tyres.
NOTE 2 Figure 2 illustrates the different texture ranges, with approximate limits regarding their effects on vehicle-
pavement interactions.
[ISO 13473-2:2002]


Key
λ texture wavelength
f spatial frequency, cycles/m
sp
NOTE A lighter shade indicates a favourable effect of texture over this range, and a darker shade indicates an
unfavourable effect.
Figure 2 — Ranges in terms of texture wavelength and spatial frequency of texture and unevenness
and their most significant, anticipated effects
© ISO 2009 – All rights reserved 3

---------------------- Page: 15 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
3.2.2
macrotexture
pavement macrotexture
deviation of a pavement surface from a true planar surface with the characteristic dimensions along the
surface of 0,5 mm to 50 mm, corresponding to texture wavelengths with one-third-octave bands including the
range 0,63 mm to 50 mm of centre wavelengths
NOTE 1 Peak-to-peak amplitudes may normally vary in the range 0,1 mm to 20 mm. This type of texture is the texture
which has wavelengths of the same order of size as tyre tread elements in the tyre/road interface. Surfaces are normally
designed with a sufficient macrotexture to obtain a suitable water drainage in the tyre/road interface. The macrotexture is
obtained by suitable proportioning of the aggregate and mortar of the mix or by surface finishing techniques.
NOTE 2 Based on physical relations between texture and friction/noise, etc., the World Road Association (PIARC),
originally defined the ranges of micro-, macro- and megatexture (Reference [9]). Figure 2, which is a modified version of
the original PIARC figure, illustrates how these definitions cover certain ranges of surface texture wavelength and spatial
frequency. Note that ride discomfort includes effects experienced in and on motorized road vehicles and bicycles, as well
as wheelchairs and other vehicles used by disabled people.
NOTE 3 Adapted from ISO 13473-2:2002.
3.2.3
megatexture
pavement megatexture
deviation of a pavement surface from a true planar surface with the characteristic dimensions along the
surface of 50 mm to 500 mm, corresponding to texture wavelengths with one-third-octave bands including the
range 63 mm to 500 mm of centre wavelengths
[ISO 13473-2:2002]
NOTE Peak-to-peak amplitudes normally vary in the range 0,1 mm to 50 mm. This type of texture is composed of
wavelengths with the same order of size as a typical tyre/road interface and is often created by potholes or ripples in the
surface. It is usually an unwanted characteristic resulting from defects in the surface. Surface roughness with longer
wavelengths than megatexture is referred to as unevenness and typically takes the form of undulations in the surface.
3.2.4
unevenness
pavement unevenness
deviation of a pavement surface from a true planar surface with the characteristic dimensions along the
surface of 0,5 m to 50 m, corresponding to wavelengths with one-third-octave bands including the range
0,63 m to 50 m of centre wavelengths
NOTE 1 Pavement characteristics at wavelengths longer than 0,5 m are considered to be above that of texture and are
referred to here as “unevenness”. For airfield applications, even wavelengths longer than 50 m would be considered.
[ISO 13473-2:2002]
NOTE 2 Longitudinal unevenness is a type of surface roughness which, through vibrations, affects ride comfort in, and
road holding of, vehicles. Transverse unevenness, e.g. due to the presence of ruts, affects safety through lateral instability
and water accumulation. It is not the intention of this part of ISO 13473 to include terms which are specifically related to
[1] [3] [4] [6]
unevenness. Such terms are defined in ISO 8608 , ISO 16063-1 , ASTM E 950-98 , and EN 13036-5 .
3.3 Megatexture measurement method
3.3.1
profilometer method
method in which the profile of a pavement surface is measured and the data used for calculation of certain
mathematically defined measures
NOTE In most cases, the profile is recorded for subsequent analysis, in some cases it may be used only in real-time
calculations.
[ISO 13473-2:2002]
4 © ISO 2009 – All rights reserved

---------------------- Page: 16 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
3.4 Terms and parameters related to spectrum analysis of texture profiles
NOTE These terms and their applications are further described in ISO/TS 13473-4.
3.4.1
texture spectrum
spectrum obtained when a profile curve has been analysed by either digital or analog filtering techniques in
order to determine the magnitude of its spectral components at different texture wavelengths (see 3.4.2) or
spatial frequencies (see 3.4.3)
NOTE 1 A texture spectrum presents the magnitude of each spectral component as a function of either texture
wavelength or spatial frequency.
NOTE 2 Adapted from ISO 13473-2:2002.
3.4.2
texture wavelength
λ
quantity describing the horizontal dimension of the irregularities of a texture profile
[ISO 13473-2:2002]
NOTE 1 Texture wavelength is normally expressed in metres or millimetres.
NOTE 2 Wavelength is a concept commonly used and accepted in electrotechnical and signal-processing vocabularies.
Since many users of this part of ISO 13473 may not be accustomed to using the term wavelength in pavement
applications, and because electrical signals are often used in the analyses of road surface profiles, there is the possibility
of confusion. Hence the expression 'texture wavelength' is preferred here to make a clear distinction in relation to other
applications.
NOTE 3 The profile may be considered as a stationary, random function of the distance along the surface. By means of
a Fourier analysis, such a function may be mathematically represented as an infinite series of sinusoidal components of
various frequencies (and wavelengths), each having a given amplitude and initial phase. For typical and continuous
surface profiles, a profile analysed by its Fourier components contains a continuous distribution of wavelengths. The
texture wavelength in ISO 13473 (all parts) is the reciprocal of the spatial frequency, the unit of which is reciprocal metre,
equivalent to cycles per metre. See also 3.4.3.
NOTE 4 The wavelengths may be represented physically as the various lengths of periodically repeated parts of the
profile; see Figure 1.
3.4.3
spatial frequency
f
sp
inverse of texture wavelength (3.4.2)
NOTE 1 Spatial frequency is normally expressed in reciprocal metres, see also 3.4.2, Note 3.
NOTE 2 The term “frequency” used in the time domain (more precisely “temporal frequency”), corresponds to “spatial
frequency” in the space domain.
NOTE 3 Adapted from ISO 13473-2:2002.
3.5 Terms and parameters related to texture profile level
3.5.1
texture profile level
L
tx,λ
L
TX,λ
logarithmic transformation of an amplitude representation of a profile curve, Z(x), the latter expressed as a root
mean square value
NOTE 1 To distinguish between octave and one-third-octave bands, the subscript for L is written in capital letters when
it relates to octave bands, L , and in lower case letters when it refers to one-third-octave bands, L .
TX,λ tx,λ
© ISO 2009 – All rights reserved 5

---------------------- Page: 17 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
−6
NOTE 2 The texture profile level, in decibels, relative to a reference value of 10 m in one-third-octave bands having
−6
centre texture wavelength, λ, L , or the texture profile level, in decibels, relative to a reference value of 10 m in octave
tx,λ
bands having centre texture wavelength, λ, L , can be expressed by Equation (1):
TX,λ
2
⎫
aa
λλ
L==10 lg dB 20 lg dB⎪
TX,λ
2
a
a ⎪
ref
ref
(1)
⎬
2
aa ⎪
λλ
L==10 lg dB 20 lg dB
tx,λ
⎪
2
a
a
ref
ref ⎭
where
a is the root mean square (r.m.s) value of the vertical displacement, in metres, of the surface profile;
λ
−6
a is the reference value, i.e. 10 m.
ref
NOTE 3 Octave-band and one-third-octave band filters are specified in ISO 13473-2:2002, 4.4.
EXAMPLE L denotes the texture profile level for the one-third-octave band having a centre texture wavelength of
tx80
80 mm, see ISO 13473-2:2002, Table 1.
NOTE 4 Texture amplitudes expressed as r.m.s. values, whether filtered or not, can have a range of several
-5 -2
magnitudes; typically 10 m to 10 m. Spectral characterization of signals is used frequently in studies of acoustics,
vibrations, and electrotechnical engineering. In all those fields it is most common to use logarithmic amplitude scales. The
same approach is preferred in this part of ISO 13473.
NOTE 5 Texture profile levels in practical pavement engineering typically range from 20 dB to 80 dB with these
definitions.
NOTE 6 Adapted from ISO 13473-2:2002.
3.5.2
megatexture level
L
Me
special case of texture profile level with the profile passing through a bandpass filter encompassing all one-
third-octave bands within the megatexture range according to 3.2.3
[ISO 13473-2:2002]
3.6 Terms related to profilometer performance
3.6.1
evaluation length
l
length of a sample from a profile which has been or is to be analysed
NOTE Evaluation length is normally expressed in metres or millimetres.
[ISO 13473-2:2002]
4 Significance and use of the megatexture indicators
4.1 General
The indicator L shall always be calculated and reported to ensure comparability between measurements.
Me
Depending on the aim of the study in question and information already obtained (e.g. unevenness or
macrotexture measures), any or all of the three other indicators mentioned below may also be reported.
6 © ISO 2009 – All rights reserved

---------------------- Page: 18 ----------------------

SIST EN ISO 13473-5:2010
ISO 13473-5:2009(E)
The profilometric method described in this part of ISO 13473 enables the indicators (see 4.2 to 4.5)
characterizing the megatexture of a pavement surface to be determined.
4.2 Megatexture spectrum
This is a one-third-octave band texture spectrum covering the megatexture range and/or the adjacent ranges.
A megatexture spectrum gives a relatively complete description of the megatexture characteristics and is used
when a detailed description is needed. A spectrum covering the entire megatexture and most of the
macrotexture range is shown in Figure 3 as an example.

Key
λ texture wavelength, in millimetres
−6
L texture profile level, in decibels, relative to a reference value of 10 m
L megatexture level
Me
L texture profile level in octave bands having centre texture wavelength 63 mm
TX63
L texture profile level in octave bands having centre texture wavelength 500 mm
TX500
Figure 3 — Example of texture spectrum with indication of which bands are included
in the L and L texture levels
TX500 TX63

4.3 Megatexture level
This indicator, L , represents an overall description of defects existing in the deviation between the
Me
pavement surface and a true planar surface. Its characteristic dimensions range between 50 mm and 500 mm
along the surface (this deviation corresponds to texture wavelengths analysed in one-third-octave bands,
which include centre texture wavelengths from 63 mm to 500 mm). This indicator is used when there is a
requirement to characterize megatexture by a single measure. It covers the range of the horizontal double
headed arrow in Figure 3. For example, t
...