The LR55 Track System
Presented by
Professor Lewis Lesley
Description of The LR55 Track System
The LR55 rail track system uses:(a) a top suspended rail, bonded into
(b) precast concrete foundation troughs,
(c) laid on a compacted type one highway base (CBR > 10 %).
(d) bonded into existing pavement with grouting
LR55 Installed in Highway Pavement
(1) Reprofile pavement, road crown, crossfall etc.(2) Excavate trench ( 200mm deep & 400mm wide) for troughs
(3) Lay, compact and line bedding layer (CBR > 10%)
(4) Lay foundation troughs (to 5mm tolerance) *
(5) Hairpin join troughs longitudinally
(6) Seal troughs into highway pavement
(7) Position welded rails to line, level and gauge in troughs (0.1mm tolerence)
(8) Inject elastomeric bonding grout to fix rails into troughs
(9) LR55 tracks can be laid one rail at a time in narrow roads
* trough design franchised to local manufacturer
(2) Rapid installation ( > 100m per 8 hr. possession)
(3) Minimum relocation of utility plant under street tracks
(4) Full traffic compatability (rail and road vehicles)
(5) Low stray currents (resistivity > 1000 Ω km)
(6) Less noise and vibration (< 20Hz ~30dB, >100Hz ~50dB,nat.freq ~800Hz)
(7) Compatable with utility (maintenance) access during operating hours
(8) Transition rail available to all existing profiles
(9) 25m radius turnout design available in LR55 profile
(10) Curves down to 12m radius
(11) Cost 60 - 70% of girder rail based tracks
Testing The LR55 System (1)
Non destructive Laboratory:- Up to 80 tonne axle loads
- 120 million cycles endurance
- Half cyclic tests under water (no failures)
- Temperature -20 °C to + 60 °C range
- Foundation trough base - compacted sand
- Bonding Grout: SIKA KC330 and ALH System 6 (similar performance)
Testing LR55 system (2)
Destructive Laboratory:- 1 m void bridged - failure at 59 tonne axle load. (trough failed in tension)
- Rail pull out - 1m section 35kN required. (trough failed in tension)
Field:
- Rotherham Bus Station. 1993-1996
2.5 million axles up to 13.5 tonnes (no failure) - South Yorkshire Supertramway 1996 - present (no failure)
3 million tonnes pa. of trams at 80 km/hr & 1million tonnes of HGVs. pa.
Installation with HMRI approval