1. MASS-PRODUCTION OF SYNTHETIC SLEEPER
- Fabrication, works for sleeper and recycling
Chuou Line
Tokyo Staion JR East
Yoshihiko SATO, Dr.Eng
Railway Track System Institute
Koji MOTOI
Sekisui Chemical Co.

2. Contents 1. Introduction Use and specifications of synthetic sleeper
Fabrication
Inspection
Works for sleepers
5.1 Turnout
5.2 Sleepers on bridge
5.3 Sleepers in directly fastened track
Reuse and recycles
Concluding remarks

3. Production of synthetic sleepers
Introduction
Production of synthetic sleepers
Laying work in Austria
Synthetic sleeper is composed of long grass fibre and hard foamed urethane.
It was developed and fabricated in Japan in 1980, to ameliorate the characteristics of the wooden sleeper, especially, durability and environmental protection.

4. Turnout of #38 at Takasaki
Uses of synthetic sleeper
Turnout of #38 at Takasaki
Bridge over Tone river
Kammon tunnel
Curve in Guangzhou Metro

5. Specification High mechanical strength little water absorption
High electrical insulation
High fastening force for dog and screw spikes
Notes: JIS Z2110 (Methods of tests for wood -1994), JIS C2110 (Testing methods for electric strength of solid insulating material -1994), JIS K6911 (Testing methods for thermosetting plastics -1995)

6. Fabrication (1) – FFU plate
- Fibre reinforced Foamed Urethane

7. Surface grinding of FFU plates Painting of sleeper surface
Fabrication(2) - From FFU plates to sleepers
Accumulation of FFU plates
Surface grinding of FFU plates
Cure after gluing
Painting of sleeper surface

8. Product bending strength Glued shearing strength
Inspection – Bending strength and glued shearing
Product bending strength
Glued shearing strength

9. Dog spike pull-out test Screw spike pull-out test
Inspection – Dog spike and screw spike pull-out test
Dog spike pull-out test
Screw spike pull-out test

10. Test piece bending test
Inspection – Test piece test, specific gravity and sizes
Test piece bending test
Specific gravity
Thickness
Width
Length

11. Setting of turnout on synthetic sleepers

12. NC Processing of sleepers
Preparation of sleepers for bridge
NC Processing of sleepers

13. Reuse and recycling

14. Evaluation Excellent Good Fair Poor FFU Concrete Sleepers
Cost
Environment
Delivery Time
Productivity
Repairing
Workability
Durability
Strength
Wooden Sleepers
Concrete Sleepers
FFU
Synthetic Sleeper
Item

15. Concluding remarks
The historical developments and fundamental characteristics of the synthetic sleeper were introduced in reference [1].
As having documented and demonstrated so far, the supply of mass produced synthetic sleepers is being introduced in a controlled manufactured environment to ensure precision and accuracy of the finished product. Further, the number of different applications and uses of synthetic sleepers have been outlined in the paper. Finally, the reuse and recycling of them are introduced.
In the future more developments for actively decreasing the vibration and noise from railway track and for the specific use of synthetic material are expected.

16. Reference
[1] Takai H, Sato Y & Sato K, Japanese experiences of using and fabricating synthetic sleepers, Railway Engineering 2005.
[2] Ohi, S & Nagafugi, T, Performance of synthetic sleeper, Rail International pp ,

17. End