Dr Patrick Vanhonacker D2S International (Dynamic Engineering) Heverlee, Belgium

Transcription

1 Design, Installation and Testing of Track Systems with No Corrugation Dr Patrick Vanhonacker D2S International (Dynamic Engineering) Heverlee, Belgium

2 Design, Installation and Testing of Track Systems with No Corrugation The reported work is a work package, part of the EC Quiet-Track research project: Design and validation of track systems with reduced or no rail roughness growth More info and public deliverables:

3 Corrugation free Track systems Potential corrugation free track systems have been designed and installed in the network of Infrabel (Belgian railways) on ballasted curved tracks to replace standard concrete ties which showed heavy corrugation after 3 years operation (no grinding). Two types of systems have been considered (spacing 24 ): Type 1: resilient fasteners on concrete ties (S1) Type 2 : large ties and standard concrete ties with under tie pads (S2 and S3)

4 Tested systems S1 Elastiplus: Elastic direct fixation on concrete sleeper (curve)

5 Tested Systems S2 standard concrete tie with wavy very resilient under tie pad (curve)

6 Tested Systems S3 H-shaped wide concrete tie with standard under tie pad (curve)

7 Measurement location

8 Measurements Follow-up measurements: Before installation of new rail After installation of new rail Every 6 months (for 36 months) Acoustic pass-by measurements Rail roughness measurements Vibration measurements

9 Measurements

10 Pass-by noise measurements Microphone at 7.5 m from center track at a height of 1.2 m above the railhead

11 Pass-by noise measurement

12 Pass-by noise measurement

13 Rail roughness measurement

14 Rail roughness measurement

15 Rail roughness measurement

16 Conclusions from measurements up to date (3 years after installation) The elastic fastener solution (S1) results in small rail roughness growth The more elastic wavy tie pads (S2) in combination with a standard concrete tie show no rail roughness growth The wide ties in combination with a standard tie pad (S3) result in moderate rail roughness growth

17 Theory behind designs (EC Corrugation project and findings at TU Munchen) Criteria : 1. rail deflection during vehicle passage > 1.2 mm 2. ratio δ/y < 3% Analytical models and more complex multi-body dynamics and FE models can be used to compute these two parameters in function of vehicle characteristics, curved track geometry, vehicle speed,.

18 36 spacing with 119RE (analytical model for dynamic curving forces) fastner A B C D E F G H I J NEW k stat kn/mm k dyn kn/mm y mm y max mm mm max mm /y% max /y max % N/mm² max N/mm² load stat kn load max kn

19 36 spacing with 136RE (analytical model for dynamic curving forces) A B C D E F G H I J NEW k stat kn/mm k dyn kn/mm y y max mm mm max mm mm /y% max /y max % , max N/mm² N/mm² load stat load max kn kn

20 119RE: Fastener stiffness and spacing requirements : δ/y< 3% and y> 1.2mm spacing inch 36" 32" 30" 28" 24" 20" 24" 20" k dyn kn/mm y mm mm /y% max N/mm² load max kn

21 Conclusions from theory 36 fastener spacing with 119RE requires supports with a k dyn < 10 kn/mm (for the considered transit system) 36 fastener spacing with 136RE requires supports with a k dyn < 12 kn/mm (for the considered transit system) The greater the fastener spacing, the lower the fastener stiffness must be The lower the fastener stiffness, the higher the rail stress, but not critical

22 Results from theory and on site validations Fastener S1 has a static rail deflection =1 mm, hence to stiff to comply but imposed by fastener fatigue requirements in curve. SMALL corrugation growth. System S2 is fully compliant with y>1.2mm and δ/y < 3%. The lateral stability in the curve is given by the wavy under tie pad. NO corrugation growth. System S3 has a static rail deflection of only 0.8 mm for lateral stability. MODERATE corrugation growth. The measured behavior of the systems fully complies with the expected behavior from theory.