DD CEN TS 15901-7-2009

DD CEN/TS 15901-7:2009 ICS 93.080.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW DRAFT FOR DEVELOPMENT Road and airfield surface characteristics Part 7: Procedure for determining the skid resistance of a pavement surface using a device with longitudinal fixed slip ratio (LFCG): the GripTester®This Draft for Development was published under the authority of the Standards Policy and Strategy Committee on 31 December 2009 © BSI 2009 ISBN 978 0 580 67244 6 Amendments/corrigenda issued since publication Date Comments DD CEN/TS 15901-7:2009 National foreword This Draft for Development is the UK implementation of CEN/TS 15901-7:2009. This publication is not to be regarded as a British Standard. It is being issued in the Draft for Development series of publications and is of a provisional nature. It should be applied on this provisional basis, so that information and experience of its practical application can be obtained. Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the international organization responsible for its conversion to an international standard. A review of this publication will be initiated not later than 3 years after its publication by the international organization so that a decision can be taken on its status. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards. According to the replies received by the end of the review period, the responsible BSI Committee will decide whether to support the conversion into an international Standard, to extend the life of the Technical Specification or to withdraw it. Comments should be sent to the Secretary of the responsible BSI Technical Committee at British Standards House, 389 Chiswick High Road, London W4 4AL. The UK participation in its preparation was entrusted to Technical Committee B/510/5, Surface characteristics. A list of organizations represented on this committee can be obtained on 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. Compliance with a British Standard cannot confer immunity from legal obligations.DD CEN/TS 15901-7:2009TECHNICAL SPECIFICATION SPÉCIFICATION TECHNIQUE TECHNISCHE SPEZIFIKATION CEN/TS 15901-7 November 2009 ICS 93.080.20 English Version Road and airfield surface characteristics - Part 7: Procedure for determining the skid resistance of a pavement surface using a device with longitudinal fixed slip ratio (LFCG): the GripTester(r)Caractéristiques de surface des routes et aéroports - Partie 7 : Mode opératoire de détermination de l adhérence d un revêtement de chaussée à l aide d un dispositif à coefficient de frottement longitudinal fixe (CFLG): le GripTester Oberflächeneigenschaften von Straßen und Flugplätzen - Teil 7: Verfahren zur Bestimmung der Griffigkeit von Fahrbahndecken durch Verwendung eines Geräts mit festem Schlupfverhältnis in Längsrichtung (LFCG): der GripTester This Technical Specification (CEN/TS) was approved by CEN on 27 June 2009 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, 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 worldwide for CEN national Members. Ref. No. CEN/TS 15901-7:2009: EDD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Recommended uses 4 4 Terms and definitions .5 5 Safety 8 6 Essential characteristics .9 6.1 Principle of measurements .9 6.2 Description of GripTester® .9 7 Key Characteristics .9 7.1 General 9 7.2 Test equipment 9 7.3 Drive tyre . 10 7.4 Test tyre . 10 7.5 Pavement wetting system, water film thickness . 10 7.6 Measurement control system and recorder . 10 7.7 Parameters recorded 11 8 Test Procedure 11 8.1 Standard test conditions 11 8.2 Prior to testing 12 8.3 Routine testing 12 8.3.1 General . 12 8.3.2 Tow mode 12 8.3.3 Push mode . 12 8.4 Airfield operational testing 13 8.4.1 Towing mode . 13 8.4.2 Push mode . 13 9 Data Recording . 13 10 Calibration . 13 10.1 General . 13 10.2 Load zero/drag zero quick check 13 10.3 Vertical load and horizontal force (full calibration) . 14 10.3.1 Check/adjust the vertical load zero. 14 10.3.2 Check/adjust the vertical load gain. 14 10.3.3 Check/adjust the horizontal force zero 14 10.3.4 Check/adjust the horizontal force gain 14 10.4 Distance . 14 10.5 Water Flow rate . 14 10.6 Full manufacturer’s service and calibration 14 10.7 Correlation exercise with other devices . 14 11 Precision 14 12 Test report . 15 Bibliography . 18 DD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 3 Foreword This document (CEN/TS 15901-7:2009) has been prepared by Technical Committee CEN/TC 227 “Road materials”, the secretariat of which is held by DIN. 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, 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. DD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 4 1 Scope This Technical Specification describes a method for determining the skid resistance of a surface by measurement of the longitudinal friction coefficient LFCG. The method provides a measure of the wet skid resistance properties of a bound surface by measurement of the longitudinal friction coefficient using a continuous reading small braked wheel fixed-slip device. The test tyre is dragged over a pre-wetted pavement under controlled speed conditions while the test tyre is parallel to the direction of motion and perpendicular to the pavement. Test speeds can vary from 5 km/h to 130 km/h depending on the application. The measured values can be affected by the test speed. The method has been developed for use on paved areas such as roads and airport runways and may also be used indoors. This Technical Specification covers the operation of the GripTester. The GripTester is a device developed by Findlay Irvine Ltd in the United Kingdom that uses the braked- wheel fixed-slip principle with a small test wheel to make measurements of skid resistance continuously on airfields, roads and other surfaces. The fixed slip ratio is 15 %. A machine conforming to the general characteristics of the GripTester and the specific provisions of this Technical Specification may also be used for the tests. The skid resistance of a pavement is determined by friction measurements and measurements of pavement texture. Where measurement of pavement texture is required the standard for this measurement and the device is described in EN ISO 13473-1. 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 48, Rubber, vulcanized or thermoplastic – Determination of hardness (hardness between 10 IRHD and 100 IRHD) ISO 4662, Rubber – Determination of rebound resilience of vulcanizates 3 Recommended uses The method is applicable to the following types of pavements, for example:  road surfacings;  road markings;  airport runways;  flight decks;  footways; DD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 5  pedestrian precincts;  test panels of surfaces intended for any of the above. The device may be used for the following fields of application:  monitoring of networks (pavement management);  approval of new surfacing;  measurements for project-level compliance;  investigation of surface skid resistance;  comparative measurements among different devices;  research measurements. 4 Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1 friction resistance to relative motion between two bodies in contact NOTE The frictional force is the force which acts tangentially in the contact area. 4.2 skid resistance characterisation of the friction of a road surface when measured in accordance with a standardised method 4.3 wet road skid resistance property of a trafficked surface that limits relative movement between the surface and the part of a vehicle tyre in contact with the surface, when lubricated with a film of water NOTE Factors that contribute to skid resistance include the tyre pressure, contact area, tread pattern, and rubber composition; the alignment, texture, surface contamination, and characteristics of the road surface; the vehicle speed; and the weather conditions. The skid resistance of a road surface in Europe varies seasonally. Generally, wet skid resistance is higher in winter as a result of the effects of wet detritus and the effects of frost and wear by tyres on microtexture and macrotexture. Wet skid resistance is lower in summer as a result of dry polishing by tyres in the presence of fine detritus. The change in skid resistance of a surface in service is affected by the volume of traffic and the composition of the traffic, i.e. cars, buses, commercial vehicles of different sizes, as the tyres of these vehicles polish and/or wear away the surfacing material in different ways. The geometry of the road will affect the change in skid resistance. Generally, tyres polish less on straight roads than on bends. Where the surface contains aggregate with a coating of binder, e.g. bitumen, resin or Portland cement, the skid resistance will change as the coating is worn away by tyres. 4.4 pedestrian slip resistance property of the trafficked surface to maintain the adhesion of a pedestrian shoe sole DD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 6 4.5 bound surface top layer or surface course of a road with the aggregates secured permanently in place NOTE Aggregates are commonly secured in place by bitumen or Portland cement. 4.6 operating speed speed at which the device traverses the test surface 4.7 contact area overall area of the road surface instantaneously in contact with a tyre NOTE This term describes the overall area generally covered by the tyre. Due to the effects of surface texture or any tyre tread pattern, not all of the tyre or road surface in the contact area can be in contact at any instant. 4.8 slip speed relative speed between the test tyre and the travelled surface in the contact area 4.9 slip ratio slip speed divided by the operating speed NOTE For devices meeting the requirements of this Technical Specification the slip ratio is fixed by the geared braking system of the test wheel. 4.10 fixed slip condition in which a braking system forces the test wheel to roll at a fixed reduction of its operating speed 4.11 braked wheel friction tester apparatus that can be moved over the test surface at a known, steady speed and that includes a test wheel, a system for braking the test wheel and instrumentation for measuring the resulting friction between the test tyre and test surface 4.12 vertical force load force applied by the wheel assembly on the contact area NOTE Some devices use an assumed load based on the static load. 4.13 horizontal force drag force acting tangentially on the test wheel in line with the direction of travel 4.14 GripTester device developed by “Findlay Irvine Ltd in the United Kingdom” in the form of a trailer which can be towed by a vehicle that contains the recording and control computer and a water supply, which is not manufactured under license 4.15 instantaneous LFC drag divided by the vertical load DD CEN/TS 15901-7:2009 CEN/TS 15901-7:2009 (E) 7 4.16 longitudinal friction coefficient LFC ratio between horizontal force (drag) and vertical load (load) for a braked wheel in controlled conditions, which is normally a decimal number quoted to two significant figures NOTE LFC varies depending on the slip ratio of the device and the operational speed. 4.17 LFCG LFCG measured by a small braked wheel fixed slip device meeting the requirements of this Technical Specification NOTE 1 It is the mean of a number of instantaneous friction readings over a defined length. NOTE 2 The range of the LFCG is 0,00 to 1,20. 4.18 sampling length distance over which responses of the sensors are sampled to determine a single measurement of the recorded variables NOTE 1 The sampling length depends upon the detailed operation of device and its recording system; a number of samples may be combined to determine a measurement for a subsection. NOTE 2 This should not be confused with horizontal resolution which is the shortest distance over which a change in the measured parameter can be detected. 4.19 subsection defined length of surface for which one set of the measured variables is reported by the device NOTE Different devices may use different subsections depending on the context of the measurements, such as 1 m, 5 m, 10 m or 20 m. 4.20 test section length of road between defined points (e.g. location references, specific features, or measured distances) comprising a number of subsections over which a continuous sequence of measurements is made 4.21 water delivery system system for depositing a given amount of water in front of the test tyre so that it then passes between the tyre and the surface being measured 4.22 water flow rate rate at which water is deposited on the surface to be me