Composite railroad ties are also called synthetic sleepers. It was created to replace traditional timber railroad ties with concrete ties. Wooden sleepers are easy to rot, or break, and have a short service life. A lot of maintenance work is needed resulting in higher costs. Besides, the exhaustion of wood resources urgently needs to be controlled and protected. According to calculation, using one synthetic sleeper can reduce the amount of wood used by one cubic meter. The concrete sleeper is heavy and can’t be installed in a special section of the railroad track. On the contrary, composite railroad ties are lightweight, eco-friendly (can be recycled), and have many other advantages.
Application of composite railroad ties
First developed by Japan’s Sekisui Chemical in the late 1970s, the synthetic sleeper has now been more and more used on all types of rail transport systems, particularly on switches, turnouts, bridges, and other projects in high-speed and metro railway construction.
AGICO manufactures first-class synthetic sleepers approved by authorities. Our patented products have been installed on many metro systems in Taiwan, Hong Kong, Guangzhou, Nanjing, etc. AGICO’s composite railroad ties can be used as the equivalent of Japan Sekisui sleepers, but with a more competitive price.
In the past years, AGICO has cooperated with many metro companies in synthetic sleeper projects in and outside China. The high performance, low cost, and excellent after-sales service have gained the approval of our clients.
Advantages of composite railroad ties
- Lightweight with high strength, insulation, and corrosion resistance.
- Less water absorption, better electrical insulating properties, better resistance to ultraviolet aging and corrosion, better oil resistance, heat resistance, and fire resistance.
- Long-period strength and dimensional accuracy maintenance.
- The field processing (fluting, drilling, abrade, nailing, bonding, and varnishing) of the synthetic sleeper is easier than that of wood.
- High spike and screw pull-out strength for the new or repaired sleeper.
- High antifatigue ability and durability.
Properties of synthetic sleeper Made by AGICO
| Item | JIS E1203:2007 Strength | (CJ/T399-2012) AGICO Sleeper Strength | |
| Material Strength | Bending Strength | min. 70 N/mm2 | min. 80 N/mm2 |
| Young’s modulus in flexure | min. 6000 N/mm2 | min. 7000 N/mm2 | |
| Withstand bending load | min. 170 kN | min. 170 kN | |
| Longitudinal compressive strength | min. 40 N/mm2 | min. 50 N/mm2 | |
| Shearing strength | min. 7 N/mm2 | min. 7 N/mm2 | |
| Adhesion shearing strength | min. 7 N/mm2 (base-material breakage) | min. 7 N/mm2 (base-material breakage) | |
| Electrical Properties | Alternating-current breakdown voltage | min. 20 kV | min. 20 kV |
| Direct-current insulation resistance | min. 1 X 1010 Ω | min. 1 X 1010 Ω | |
| Pulling Strength | Track spike pulling strength | min. 15 kN | min. 20 kN |
| Screw spike pulling strength | min. 30 kN | min. 40 kN | |
| Unit volume mass | 0.74± 0.1 g/cm3 | 0.74± 0.1 g/cm3 | |
| Amount of water absorption | max. 10 mg/cm2 | max. 10 mg/cm2 | |
The material of composite railroad ties
The composite railroad ties are mainly referred to as Fiber-reinforced Foamed Urethane synthetic sleepers. It is made of rigid polyurethane reinforced with continuous glass fiber through a pultrusion process. The main materials contain continuous glass fiber, polyether polyol, isocyanate, and related components. Using fiber/glass-reinforced composite materials can get high insulation and corrosion resistance to avoid chemical or biological corrosion. The appearance of the synthetic sleeper is similar to a wooden sleeper. It has all the advantages of the wood and plastic sleeper.
Studies have shown that the physical properties of synthetic sleepers have hardly changed after 15 years of application. In Japan, synthetic sleepers have been successfully used for nearly 20 years. Compared with concrete turnout sleepers, composite railroad ties have good flexibility and help reduce vibration and noise. It can adapt to high-speed tracks even without rail pads. Its specific gravity is only one-third of that of concrete. Also, composite materials can be recycled. After waste is crushed and pressurized, new recycled products can be made.
Synthetic sleeper processing
AGICO supplies synthetic sleepers that comply with domestic or foreign standard sizes (any dimensions based on customers’ requests). We can machine groove on the side of the sleeper, drill holes on the top of the sleeper, or any other shapes as per the customer’s design.
Synthetic sleepers can also be pre-fabricated with rail to be installed on-site rapidly. It can be processed on-site to ensure installation accuracy and speed.
Workshop Overview
