ISO INTERNATIONAL STANDARD 20138-1 First edition 2018-10 Railway applications Calculation of braking performance (stopping, slowing and stationary braking) Part 1: General algorithms utilizing mean value calculation Applicationsferroviaires-Calculdesperformancesdefreinage (freinage d'arret, de ralentissement etd'immobilisation) Partie1:Algorithmes generaux utilisantle calcul parla valeurmoyenne Referencenumber IS020138-1:2018(E) ISO @IS0 2018 IS020138-1:2018(E) COPYRIGHTPROTECTEDDOCUMENT IS02018 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone:+41227490111 Fax: +41 22 749 09 47 Email: copyright@iso.org Website: www.iso.org Published in Switzerland ii @ IS0 2018 - All rights reserved IS020138-1:2018(E) Contents Page Foreword ..V Introduction. ..i. 1 Scope. 2 Normative references 3 Terms and definitions 4 Symbols. 5 Stopping and slowing distances calculation ..7 5.1 General .7 ..8 5.2 Vehicle characteristics 5.2.1 Static mass, mst .8 5.2.2 Equivalent rotating mass, mrot. .8 5.2.3 Dynamic mass, mdyn. .9 5.2.4 Wheel diameter. ..9 5.3 Adhesionwheel/raildependentbrakeeguipmenttypecharacteristics 9 5.3.1 Basicbrakecvlinder. .9 5.3.2 .11 Tread brake. 5.3.3 Tread brake unit ..13 5.3.4 Disc brake. .15 5.3.5 Electro-dynamic brake. .17 5.3.6 Fluid retarder. ..18 5.3.7 Transmission retarder .18 5.3.8 Rotating eddycurrentbrake .18 5.4 Adhesion independentbrakeequipmenttypecharacteristics .18 5.4.1 Magnetic track brake. ..18 5.4.2 Linear eddy current brake. .19 5.4.3 Mean retardingforcebytrainresistance. .20 5.4.4 Aerodynamic brake. 21 5.4.5 Electrodynamicbrakegenerated by linear induction motor .21 5.5 Time characteristics. 21 5.5.1 Derivationofbrakeequipmenttimecharacteristics .21 5.5.2 Equivalent responsetime, te. 21 5.6 Initial and operating characteristics .23 5.6.1 Forces on the slope.. 23 5.6.2 Downhill forcedue togravity depending on thegradient 24 5.6.3 Blending 25 5.6.4 Valueofthemeanadhesion required betweenwheel/railforthebraked wheelset .26 5.7 Stoppingandslowingdistancecalculationbasedonmeanvalues .27 5.7.1 Mean retardingforcewith respect to thedistance .27 5.7.2 Equivalent deceleration, ae,based on retardingforces .27 5.7.3 Equivalentfreerunning distance, so. .28 5.7.4 Stopping and slowing distance on level track .28 5.7.5 Stopping and slowing distance based on different gradients .29 5.8 Supplementary dynamic calculations. .30 5.8.1 General. .30 5.8.2 Braking energy ..31 5.8.3 Maximum braking power of each brake equipment type, Pmax,n .32 Stationary braking. .32 6 .32 6.1 General 6.2 Holding brake. .32 6.3 Immobilization brake. .32 6.4 Parking brake. .32 iii IS0 2018-All rights reserved