urban track singapore

URBAN TRACK Final Conference Alternative to Floating Track Slab

High Attenuation Sleeper

Presented by Ian Robertson, ALSTOM24 June 2010, Prague

Final Conference – 24 June 2010 2

Contents

Specific objectives of study

Chosen concept

Detailed design and laboratory test

Site test (ongoing)

Conclusions


Specific objectives of study

Develop slab track with following technical characteristics

metro environment (18t axle load, 100 kph)

equivalent vibration performance to Floating Slab Track

ability to meet all railway constraints

Safety (derailment) including track level evacuation

Comfort

maintenance

Construction method

for standard equipment and methods

production rate as conventional track slab

Lower costs compared to AFST

For capital portion (design+procure+build)

For maintenance portion


Chosen conceptReview of existing systems worldwidePrevious generation bi-block sleepers for CTRL

Relatively low weight Tie bar overstressed with very soft pads Track gauge variations with very soft pads

Chosen concept = mono-block resilient sleeper High attenuation due to

High sleeper mass (350 –

400 kg)Very soft resilient inserts (8KN/mm/fastener)

Adapted to tracklaying gantriesMaintenance friendly


Detailed design and laboratory testHAS mono-bloc sleeper concept

Rigid boot

Concrete sleeperFastening

system according

to customer

choicesealing

Holes for conductor rail support



Comparison of Different Antivibratile System

-60

-50

-40

-30

-20

-10

0

10

201

1,6

2,5 4

6,3 10 16 25 40 63 100

158

251

Frequency (Hz)

Inse

rtio

n G

ain

(dB

)

Insertion Gain SFS 312 (dB)

Insertion Gain DFC Pandrol (dB)

Insertion Gain CTRL 2(dB)

Insertion Gain FST (Taipei) (dB)

Insertion Gain EGG_2(dB)

Insertion gain target



DESIGN FULLY COMPLIANT WITH MOST RAIL FASTENERS

Typical tunnel layout



Based on OBLEX project 20 cm gain

Dia.5.8 Dia. 5.6

Typical case of impact on tunnel diameter



Time

Load 2 Hz

5 HzFmax

.Fmax

Actual load diagram with sine shape

Optimum load diagram with triangle shape simulating wheel passage

Simplified load diagram used during fatigue test to simulate bogie passage

ACHIEVED 4,5 MILLIONS LOAD CYCLE WITH SUCCESS

HAS mono-bloc sleeper dynamic testing regime



Mechanical test carried out Fatigue test with inclined loads according to the

following phases :

1M Cycles @ low frequency (3 Hz) applied load between 10kN et 75kN, centred, inclined at 38°

0.5MCycles @ moderate frequency (5 Hz) applied load between 30/40kN et 75kN centred , inclined at 38°

2M Cycles @ low frequency (3 Hz) applied load between 10kN et 75kN, inclined at 10°

and 38°

1 M Cycles @ moderate frequency (5 Hz) applied load between 30/40kN et 75kN, inclined at 10°

and 38°

NO PAD WEARING & NO VERTICAL STIFFNESS LOSS AFTER 4.5M CYCLES

(EN13230: 2M CYCLES)



EXCITATIO N

MONOBLOC SLEEPER

RAIL

RIGID HULL

RAIL

PRELOAD

CONCRETE BASE

SENSOR S

Testing arrangementsAcoustic test

mechanical test



0

2

4

6

8

10

12

MN/m

0 32 40 50 64kN

Stifffness vs static load at 8Hz

K (MN/m)

Dynamic test results


Site test (ongoing)

Several possibilities reviewed notably SINGAPORE Circle LineCEF test site (Valenciennes)

CEF chosen Easier logistics To respect URBAN TRACK timing

Construction just completed June 11

Vibration tests scheduled July

Introduction


Site test -

Situation

Test section• 190m radius• 160mm cant

Situation within CEF site

Actual track to replace

• ballasted track

• fishplated U50 rail

•

good ground conditions EV2 above 80 MPA


Site test

50m of High

Attenuation

Track 2 x 6.5m of transition slab with ballasted track Sleeper spacing

700mm

Welded

rail on high attenuation zone Fishplated

joints allowing

movement

at

each

end of test

General Layout


Site test Typical section


Site test

Detailed design concept

230

230

80

2583 80 200

Reinforced

U-shaped foundationTrack «

slab

»

concrete

unreinforced With frequent joints to avoid shrinkage cracking


Site test

After

HAS vibration testingAxle

load

= 25 tonnes

Total load = 280MGT HAS resilient

inserts to replace by stiffer inserts

(30MN/M)

Structural design based on Eurocode

2 Load

Model 71

Crack 0.2mm

Detailed design assumptions


Site test

Neighbouring (existing) ballast track

Total dynamic

stiffness

around

80kN/mm per

fastener

High

Attenuation

Sleeper Track

Under sleeper pad

= 1,5*8 kN/mm

Total stiffness = 11kN/mm per

fastener

Transition zone

Target total stiffness

= 46kN/mm

Under sleeper pad

= 70 to 80 kN/mm per

fastener

Total stiffness

= 47 to 52 kN/mm per

fastener

0.70.6 0.7

HAS Track

Ballast track

Transition zone

70.7

Transition slab design


Site test Construction after concreting of foundation


Site testConstruction before track slab concreting


Site test

In July testing of following zonesHAS track Transition track

Static measurements

Soil impedance

Unloaded and loaded track impedanceDetermination of in situ HAS track characteristics

Rail surface quality

Testing


Site test

Dynamic measurements (6 pass-bys) train induced

vibration levels

on track slab concrete

outside U shaped foundation

rail and sleeper deflection

of both rails rail and sleeper lateral displacements

Testing


Site test

Strain measurementsCaptors on rail foot 5 sleeper spacing per measurement site

Testing


Site test

Vibration simulationHAS track

parameters

measured

PACT reference

track

parametersMeasured

roughness

Rolling

Stock data Insertion gain calculation

in 1/3rd octave bands

Testing


Conclusions

High performance alternative to floating track slab

Ideal for underground metro applications

Could absorb railway loads applied to sensitive bridges

In high speed tunnel application

Theoretically compared to “S3”

high speed –4dB (halved the vibration level)

Limiting operational criteria (mixed operations, speed, twist…) to determine

Costing being completed but ballpark figures are

Compared to typical metro floating track slab

Design, procure and build cost HAS gives 10% saving

Maintenance costs for HAS are much lower

Potential to reduce tunnelling costs

Further information

final report will be ready after completion of CEF tests in August 2010

See URBAN TRACK website http://www.urbantrack.eu/

RGCF no 191 February 2010

Railway Engineering 2009

High Attenuation Sleeper

http://www.urbantrack.eu/