ASTM_F_3189_-_17.pdf

Designation:F318917Standard Test Method forMeasuring Force Reduction,Vertical Deformation,andEnergy Restitution of Synthetic Turf Systems Using theAdvanced Artificial Athlete1This standard is issued under the fixed designation F3189;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method specifies a method for measuring forcereduction,vertical deformation,and energy restitution of syn-thetic turf surfaces.1.2 This method is used to characterize properties of syn-thetic turf systems including the turf fabric,infill material,andshock pad(if applicable).1.3 It can be used for characterizing synthetic turf systemsin laboratory environment or in the field.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 energy restitution(ER),na measure of the energyreturned by the synthetic turf surface after the impact force hasbeen applied.2.1.2 energy restitution coeffcient,nthe ratio of the dy-namic load energy applied to the surface to the energy returnedby the surface.2.1.3 force reduction(FR),nthe ability of a synthetic turfsports surface to reduce the impact force of a mass falling ontothat surface.2.1.3.1 DiscussionThe reduction in impact force for thistest method is expressed as a percentage reduction whencompared to a reference force of 6760 N.The reference forceis the theoretical maximum impact force that occurs when thetest is performed on a rigid surface(concrete).2.1.4 synthetic turf system,nall components of the syn-thetic turf surface and subsurface that have the potential toinfluence the dynamic properties of the surface.2.1.4.1 DiscussionThese include any shock pads or dy-namic base constructions installed as part of the synthetic turfsystem.2.1.5 vertical deformation(Def),na measure of the dis-tance a test foot penetrates into the surface when a standardimpact force is applied.2.2 Symbols:2.2.1 Aacceleration in m/s2.2.2.2 Defdeformation in millimeters.2.2.3 Eenergy in Joules.2.2.4 ERenergy restitution.2.2.5 Fforce in Newtons.2.2.6 FRforce reduction in%.2.2.7 gacceleration due to gravity.2.2.8 Rcoefficient of restitution.2.2.9 ttime in seconds.3.Summary of Test Method3.1 A mass with a spring attached is allowed to fall onto thetest surface.The acceleration of the mass is recorded from themoment of release until after its impact with the turf surface.Force Reduction is the percentage reduction in the measuredmaximum force(Fmax)relative to the reference force(Fmax).3.2 Deformation is calculated by double integration of therecord of acceleration versus time.Energy restitution is calcu-lated from the force versus deformation curve.4.Significance and Use4.1 The dynamic interaction between the athlete and thesynthetic turf surface affects the comfort and the performanceof the athlete.Interaction with a surface that has low amountsof deformation and shock absorption allows the player to runfast and turn quickly,but has the potential to cause discomfortand damage to the lower extremity joints.Synthetic turf1This test method is under the jurisdiction of ASTM Committee F08 on SportsEquipment,Playing Surfaces,and Facilities and is the direct responsibility ofSubcommittee F08.65 on Artificial Turf Surfaces and Systems.Current edition approved Jan.1,2017.Published February 2017.DOI:10.1520/F3189-17.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 surfaces having high deformation have lower energy restitu-tion.Less of the energy exerted by the athlete returns from thesurface,possibly increasing the fatigue for the performingathlete.5.Test Conditions5.1 Laboratory Test Conditions:5.1.1 Laboratory tests shall be conducted on samples of thecomplete turf system.The test sample shall have nominaldimensions of 1 m by 1 m.The turf samples shall be preparedin accordance with the manufacturers stated method.5.1.2 Characteristics of the Laboratory FloorThe labora-tory floor shall be concrete with a minimum thickness of 100mm.5.1.3 Conditioning and Test TemperatureThe test pieceshall be c