SIST-TS CEN/TS 16717:2015
(Main)Surface for sports areas - Method of test for the determination of shock absorption, vertical deformation and energy restitution using the advanced artificial athlete
Surface for sports areas - Method of test for the determination of shock absorption, vertical deformation and energy restitution using the advanced artificial athlete
This Technical Specification specifies a method of test for measuring the shock absorption, vertical deformation, and energy restitution characteristics of sports surfaces. It is not considered appropriate for rigid sports surfaces that have shock absorbing properties of 10 % FR or less.
Sportböden - Prüfverfahren zur Bestimmung des Kraftabbaus, der vertikalen Verformung und der Energierückgabe mit dem weiterentwickelten künstlichen Sportler
Diese Technische Spezifikation legt ein Verfahren zur Bestimmung des Kraftabbaus, der vertikalen Verformung und der Energierückgabeeigenschaften von Sportböden fest. Das Verfahren ist nicht für starre Sportböden mit einem Kraftabbau entsprechend einer Kraftverringerung von 10 % oder weniger geeignet.
Sols sportifs - Méthode d'essai pour la détermination de l'absorption des chocs, de la déformation verticale et de la restitution d'énergie à l'aide de l'athlète artificiel avancé
La présente Spécification technique spécifie une méthode d'essai pour le mesurage des caractéristiques d'absorption des chocs, de déformation verticale et de restitution d'énergie des sols sportifs. Elle est jugée inappropriée pour les sols sportifs rigides présentant des caractéristiques d'absorption des chocs donnant une réduction de force de 10 % ou moins.
Površine za športne dejavnosti - Metode preskušanja in ugotavljanja ublažitve udarca (sunka), navpične deformacije in povratne energije pri sintetičnih talnih oblogah
Ta tehnična specifikacija določa metodo preskušanja za merjenje ublažitve udarca, navpične deformacije in povratne energije športnih površin. Ni ustrezna za toge športne površine, ki imajo lastnosti ublažitve udarca 10 % FR ali manj.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN/TS 16717:2015
01-maj-2015
3RYUãLQH]DãSRUWQHGHMDYQRVWL0HWRGHSUHVNXãDQMDLQXJRWDYOMDQMDXEODåLWYH
XGDUFDVXQNDQDYSLþQHGHIRUPDFLMHLQSRYUDWQHHQHUJLMHSULVLQWHWLþQLKWDOQLK
REORJDK
Surface for sports areas - Method of test for the determination of shock absorption,
vertical deformation and energy restitution using the advanced artificial athlete
Sportböden - Prüfverfahren zur Bestimmung des Kraftabbaus, der vertikalen Verformung
und der Energierückgabe mit dem weiterentwickelten künstlichen Sportler
Sols sportifs - Méthode d'essai pour la détermination de l'absorption des chocs, de la
déformation verticale et de la restitution d'énergie à l'aide de l'athlète artificiel avancé
Ta slovenski standard je istoveten z: CEN/TS 16717:2015
ICS:
59.080.60 Tekstilne talne obloge Textile floor coverings
97.220.10 Športni objekti Sports facilities
SIST-TS CEN/TS 16717:2015 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN/TS 16717:2015
TECHNICAL SPECIFICATION
CEN/TS 16717
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
March 2015
ICS 59.080.60; 97.220.10
English Version
Surface for sports areas - Method of test for the determination of
shock absorption, vertical deformation and energy restitution
using the advanced artificial athlete
Sols sportifs - Méthode d'essai de détermination de Sportböden - Prüfverfahren zur Bestimmung des
l'absorption des chocs, de la déformation verticale et de la Kraftabbaus, der vertikalen Verformung und der
restitution d'énergie, au moyen de l'athlète artificiel amélioré Energierückgabe mit dem weiterentwickelten künstlichen
Sportler
This Technical Specification (CEN/TS) was approved by CEN on 14 July 2014 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 16717:2015 E
worldwide for CEN national Members.
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Contents Page
1 Scope .5
2 Normative references .5
3 Terms, definitions and symbols .5
3.1 Terms and definitions .5
3.2 Symbols .6
4 Principles .6
5 Test specimens .6
5.1 General .6
5.2 Point-elastic and mixed-elastic sports surfaces .6
5.3 Area-elastic and combined-elastic sports .7
5.4 Synthetic turf and textile sports surfaces .7
6 Laboratory tests conditions .7
6.1 Characteristics of the laboratory floor .7
6.2 Conditioning and Test Temperature .7
7 Site tests conditions .7
8 Test Apparatus .7
9 Verification of impact speed . 10
9.1 General . 10
10 Checking of force on concrete . 11
11 Test procedure . 11
11.1 General . 11
11.2 Method A . 11
11.3 Method B . 12
11.4 Calculation of Shock Absorption and expression of results . 12
11.5 Calculation of Deformation and expression of results . 12
11.6 Calculation of Energy Restitution and expression of results . 13
11.7 Checking of the algorithm . 14
Annex A (informative) Positions for laboratory tests on test specimens of indoor area elastic and
combined floor . 15
A.1 General . 15
A.2 Area-elastic sports floor with elastic construction (Figures A.1 to A.5) . 15
A.2.1 Key . 15
A.2.2 Positioning of the system measuring spots . 15
A.3 Area-elastic sports floor with elastic construction (Figures A.6 to A.10) . 17
A.3.1 Key . 17
A.3.2 Positioning of the system measuring spots . 18
A.4 Area-elastic sports floor with elastic construction (Figures A.11 to A.15) . 20
A.4.1 Key . 20
A.4.2 Positioning of the system measuring spots . 20
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A.5 Area-elastic sports floor with elastic construction (Figures A.16 to A.19) . 22
A.5.1 Key . 22
A.5.2 Positioning of the system measuring spots . 22
A.6 Area-elastic sports floor with elastic construction (Figures A.20 to A.23) . 23
A.6.1 Key . 24
A.6.2 Positioning of the system measuring spots . 24
A.7 Area-elastic sports floor with elastic construction (Figures A.24 to A.25) . 25
A.7.1 Key . 25
A.7.2 Positioning of the system measuring spots . 25
A.8 Site test . 26
A.9 Positioning of the system measuring spots for indoor point elastic and mixed floors . 27
A.9.1 Laboratory test . 27
A.9.2 Site test . 27
A.10 Positioning of the system measuring spots for surface for sports areas (EN 14877 and
EN 15330). 27
A.10.1 Laboratory test . 27
A.10.2 Site test . 27
Annex B (normative) Expression of results . 28
Annex C (informative) Example of raw data and theoretical results to check algorithm . 29
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Foreword
This document (CEN/TS 16717:2015) has been prepared by Technical Committee CEN/TC 217 “Surfaces for
sports areas”, the secretariat of which is held by AFNOR.
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 announce this Technical Specification: 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
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1 Scope
This Technical Specification specifies a method of test for measuring the shock absorption, vertical
deformation, and energy restitution characteristics of sports surfaces. It is not considered appropriate for rigid
sports surfaces that have shock absorbing properties of 10 % FR (Force reduction) or less.
2 Normative references
The following documents, in 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 12229, Surfaces for sports areas - Procedure for the preparation of synthetic turf and needle-punch test
pieces
EN 12504-2, Testing concrete in structures - Part 2: Non-destructive testing - Determination of rebound
number
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
shock absorption (SA)
ability of a sports surface to reduce the impact force of a body falling onto the surface
Note 1 to entry: This reduction in impact force is expressed as a percentage reduction in force (Force Reduction)
when compared to a reference force of 6760 N, which is the theoretical maximum impact force that could occur when the
test is undertaken on a rigid non shock absorbing surface (e.g.) concrete.
3.1.2
deformation (D)
measure of how far a test foot compresses or penetrates into the surface when a standard impact force is
applied
3.1.3
energy restitution (ER)
measure of the energy returned by the sports surface after the impact force has been applied
3.1.4
energy restitution coefficient
ratio of the dynamic load energy applied to the surface to the energy returned by the surface (R)
3.1.5
sports surface
all components including the playing surface and sub-surface that may influence the dynamic properties of the
surface. These may include shockpads or ‘dynamic base constructions for synthetic turf systems, battens and
sub-assemblies for indoor flooring structures, etc
3.1.6
point elastic sports surface
sports floor, to which the application of a point force causes deflection only at or close to the point of
application of the force
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3.1.7
mixed elastic sports surface
point-elastic sports floor with a synthetic area-stiffening component
3.1.8
area elastic sports surface
sports floor, to which the application of a point force causes deflection over a relatively large area around the
point of application of the force
3.1.9
combined elastic sports surface
area-elastic sports floor with a point-elastic top layer, to which the application of a point force causes both
localized deflection and deflection over a wider area
3.2 Symbols
The following symbols are used in formulas and text throughout this document:
F Force in Newtons;
−2
;
A Acceleration in ms
g Acceleration due to gravity;
SA Shock absorption in %;
D Deformation in mm;
R Coefficient of restitution;
E Energy in Joules;
t time in second
4 Principles
A mass with a spring attached to it is allowed to fall onto the test piece and from the recorded acceleration of
the mass from the moment of release until after its impact with the test piece. The following described
parameters are calculated.
Shock absorption (SA) is the percentage reduction in the measured maximum force (F ) relative to the
max
reference force (F ).
ref
Deformation is calculated by double integration of the record of Acceleration vs. time.
Energy restitution coefficient is calculated from the Force vs. Deformation curve.
5 Test specimens
5.1 General
The test specimen shall comprise the entire sports surfacing system.
5.2 Point-elastic and mixed-elastic sports surfaces
For point-elastic and mixed-elastic sports surfaces the test piece shall be a piece of the surface of minimum
size 1,0 m by 1,0 m, in combination with the supporting layers to be used in service and using the
recommended method of attachment in accordance with the manufacturer’s instructions.
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5.3 Area-elastic and combined-elastic sports
For area-elastic and combined-elastic sports surfaces, the test piece shall be a sample of the complete
surfacing system measuring 3,5 m by 3,5 m, assembled and installed in accordance with the manufacturer’s
stated method, on a substrate complying with the manufacturer’s requirements.
5.4 Synthetic turf and textile sports surfaces
Laboratory test pieces of synthetic turf and textile sports surfaces shall be prepared in accordance with
EN 12229.
6 Laboratory tests conditions
6.1 Characteristics of the laboratory floor
The laboratory test floor shall be a concrete floor of minimum thickness 100 mm. The surface hardness when
measured in accordance with EN 12504-2 shall be ≥ 40 MPa.
6.2 Conditioning and Test Temperature
For tests in the laboratory, condition the test piece for a minimum of 24 h at the test temperature. Unless
otherwise specified the test temperature shall be 23 °C ± 2 °C.
7 Site tests conditions
Tests on site shall be made at the prevailing ambient temperature and humidity, which shall be recorded and
reported.
8 Test Apparatus
8.1 The principle of the test apparatus is shown in Figure 1 and consists of the following essential
components specified in 8.2 to 8.9.
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Keys
1 guide for the falling mass
2 electric magnet
3 falling mass
4 accelerometer
5 spring
6 test foot
Figure 1 — Test apparatus
8.2 Falling mass (3), incorporating a helical metal spring and steel test foot and fitted with an
accelerometer, having a total mass of 20,0 kg ± 0,1 kg.
8.3 Helical steel spring (5), whose characteristic is linear (measured with maximum increments of 1000 N)
with a spring rate of 2000 N/mm ± 60 N/mm over the range 0,1 kN to 7,5 kN. The axis of the spring shall be
vertical and shall be directly below the centre of gravity of the falling mass. The spring shall have three coaxial
coils that shall be rigidly fixed together at their ends. The mass of the spring shall be 0,80 kg ± 0,05 kg.
8.4 Steel test foot (6) having a lower side rounded to a radius of 500 mm ± 50 mm; an edge radius of 1 mm;
a diameter 70 mm ± 1 mm and a minimum thickness of 10 mm. The mass of the test foot shall be
400 g ± 50 g.
8.5 Test frame with minimum of three adjustable supporting feet, no less than 250 mm from the point of
application of the load for point and mixed elastic surfaces and no less than 600 mm from the point of
application of the load for area and combined elastic surfaces. The design of the supporting feet shall ensure
the weight of the test apparatus is equally distributed on all the feet.
2
The pressure (with the mass) on each foot shall be less than 0,020 N/mm and the pressure (without the
2
mass) on each foot shall be greater than 0,003 N/mm .
The complete system shall have a mass of ≤ 50 kg.
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8.6 A piezo-resistive accelerometer with following characteristics:
— measuring range: ± 50 g;
— 3 dB upper frequency response: ≥ 1 kHz;
— linearity error: < 2 %.
The accelerometer shall be firmly attached to avoid natural filtering and the generation of spurious signals.
8.7 Means of supporting the mass (2) that allows the falling height to be set with an uncertainty of no
greater than 0,25 mm.
8.8 Means of conditioning and recording the signal from the acceleration sensing device and a means of
displaying the recorded signal. (see Figure 2, below):
— sampling rate minimum: 9600 Hz;
— electronic A-to-D converter with a resolution giving 1 bit equal to a maximum 0,005 g acceleration;
— signal from the acceleration-sensing device shall be filtered with a 2nd order low-pass Butterworth filter
with a cut-off frequency of 600 Hz.
8.9 Means of calculating the speed and displacement of the falling weight during the course of impact by
integration and double integration of the acceleration signal. To be verified in accordance with 9.4 and 9.5.
Key
1 Free drop phase
2 Contact phase
3 Time (s)
Figure 2 — Example of falling mass acceleration vs .time curve
— T0 time when the mass starts to fall.
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— T1 time when the test foot makes contact with the surface (determined on the Velocity / time curve – V
max
*).
— T2 time (determined on the Velocity / time curve) – V *) corresponding to the maximum velocity when
min
the mass rebounds after the impact.
NOTE Vmin and Vmax can be a minimum or maximum value depending on the sensor’s direction.
Key
1 Time (s)
Figure 3 — Example of velocity vs. time curve
9 Verification of impact speed
9.1 General
The verification should be carried out to ensure the correct impact speed (or energy, because the mass is
fixed) and the correct functioning of the apparatus.
The checking procedure shall consist of three steps and shall be carried out on a stable and rigid floor (no
2
significant deflection under a 5 kg/cm pressure) as follow:
— laboratory testing: at least once on any day on which testing is undertaken or following dismantling and
re-assembly of the test apparatus, prior to carrying out any measurements;
— site testing: following re-assembly of the test apparatus, prior to carrying out any measurements.
9.2 Set up the apparatus to ensure a free drop that is no more than ± 1° from the vertical.
Adjust the height of the lower face of the steel test foot so it is 55,00 mm ± 0,25 mm above the rigid floor.
Drop the weight on the rigid floor and record the acceleration of the falling weight till the end of the impact.
9.3 Repeat 8.1 twice, giving a total of 3 impacts.
9.4 For each impact calculate, by integration from T0 to T1 of the acceleration signal, the initial impact
velocity. Calculate the mean impact velocity of the three recordings.
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The mean impact velocity shall be in the range of 1,02 m/s to 1,04 m/s.
If the initial impact velocity is outside the specified range the test apparatus is not operating correctly and any
subsequent results obtained shall be considered invalid.
9.5 After verifying the initial impact velocity place the falling weight on the rigid floor. Measure the height
between a static reference point on the apparatus (for example the magnet) and the falling weight. The
measured height shall be used for all measurements and is designated the “lift height”.
NOTE The “lift height” will be slightly greater than 55,0 mm due to the deflection of the apparatus during operation.
10 Checking of force on concrete
At a frequency of at least once every 3 months check the force on the laboratory concrete floor to ensure the
consistency of maximum force on concrete as measured by the apparatus and the theoretical force on
concrete (6760 N).
The checking shall be carried out in accordance with 9.2 to 9.5 with the addition of F max value (see 11.4).
The mean F max of three consecutive shall be 6760 N ± 250 N.
11 Test procedure
11.1 General
Two test procedures are specified.
Method A shall be used used for surface where the setting of falling height is not possible when the precise
distance between the test specimen and the lower face of the steel test foot cannot be measured (e.g. on
synthetic or natural turf).
Method B shall be used for surface where it is possible to precisely set the falling height between the surface
of sample and the lower face of the steel test foot (e.g. on indoor sport flooring or athletic track surfacing).
To avoid influence of the operator’s weight on the results, through variation in the preload on the sports
surfacing system under test, the operator shall be positioned:
— laboratory test off the sample;
— site test (mixed or point-elastic floors) at least 1,0 m from the point of impact;
— site test (area-elastic or combi-elastic floors) at least 2,0 m from the point of impact.
If there is any doubt over the nature of the sports surface under test, the operator shall be positioned at least
2,0 m from the point of impact or off the sample.
11.2 Method A
11.2.1 Set up the apparatus so it is positioned vertically on the test sample.
11.2.2 Lower the test foot smoothly onto the surface of the test piece. Immediately after (within 10 s) set the
“lift height” described in 9.5 and re-attach the mass on the magnet.
11.2.3 After 30 (±5) s (to allow the test specimen to relax after removal of the test mass) drop the mass and
record the acceleration signal.
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11.2.4 Re-validate the lift height after the impact so that within 30 s ± 5 s the mass is lifted from the surface
and re-attached to the magnet.
11.2.5 Repeat 11.2.3 - 11.2.4 to obtain a total of 3 impacts.
11.3 Method B
11.3.1 Set up the apparatus so it is positioned vertically on the test sample.
11.3.2 Adjust the height of the lower face of the steel test foot so it is 55,00 mm ± 0,25 mm above the surface
of sample.
11.3.3 Drop the mass and record the acceleration signal.
11.3.4 Immediately after (within 10 s) re-attach the mass to the magnet.
11.3.5 After 120 (±5) s (to allow the test specimen to relax after removal of the test mass) repeat 11.3.2 to
11.3.5 two more time to obtain a total of 3 impacts.
NOTE Guidance on the number of test locations for different types of indoor sports flooring is given in Annex A.
11.4 Calculation of Shock Absorption and expression of results
Calculate the maximum force (F ) at the impact with the following formula:
max
F = m × (A + g)
max max
where
F correspond to the peak force, expressed in Newtons [N];
max
−2
A
is the peak acceleration during the impact (ms );
max
m is the calibrated mass of the falling weight (kg);
−2
g
is the acceleration due to gravity (ms ).
Calculate the Shock Absorption (SA) with the following formula:
F
max
SA= 1− ×100
6760
where
SA is the shock absorption, in %;
F
is the peak force measured on the sport surface (N).
max
Report the value of Force Reduction in accordance with Table B.1.
11.5 Calculation of Deformation and expression of results
Calculate by a double integration of a(t) on the interval [T1, T2] the displacement of the weight D (t),
weight
starting at the moment where it has reached its highest velocity (at T1).
The vertical deformation is defined (on the time interval [T1,T2] as:
VD = D - D
weight spring
where
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T2 T2
D = max A dt dt , with D = 0 m A(t) T1
weight weight
∫ ∫
T1 T0
(m× A )
max
D =
spring
C
spring
where
F is the peak force measured on the sport surface (N);
max
−2
A
is the peak acceleration during the impact, (9,81 m.s );
max
m is the calibrated mass of the falling weight (kg);
−1
C
is spring constant (Nm ) (given the certificate of calibration, and measured
spring
in the adapted range).
Report the value of Vertical Deformation in accordance with Table B.1.
11.6 Calculation of Energy Restitution and expression of results
Draw the curves F(t) and D (t) using A(t).
— F(t): Measured force on the surface vs time;
— D (t) Deformation of the surface vs time;
— A(t): acceleration signal from the sensor vs time.
On same time base, draw the curve F(D) (see Figure 4).
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Key
1 Energy absorbed
2 Energy restitued
X Deformation (mm)
Y Force (N)
Figure 4 — Example of Force vs Deformation curve
Calculate
— The impact energy by the formula:
D
max initial condition D = 0 m
0
E= F()D dD
i
∫
D
0
— The restituted energy with the formula:
D
residual
E = F()D dD
r
∫
D
max
— The coefficient of restitution, R, with the formula:
E
r
R=
E
i
Expression of the results
Report the R value in percentage following Table B.1.
11.7 Checking of the algorithm
When and known signal is entered into the test apparatus software, it shall produce a known result. An
example of known signal with associated results is provided in Annex C.
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An
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