Adif is trialling the use of synthetic sleepers to assess whether they have the potential to become a viable alternative to wooden sleepers.
Part of Adif’s innovation and sustainability strategy, the trial joins similar initiatives carried out by other railway managers across Europe, including France, Switzerland and Germany.
Network Rail, for example, laid its first recycled plastic sleepers in the summer of 2021.
Such projects bring the industry closer to achieving Sustainable Development Goal (SDG) 9, which includes the modernisation of infrastructures so that they are sustainable, using resources more efficiently and adopting environmentally sound technologies and industrial processes.
Plastic sleepers support this goal as they are made of recyclable, non-polluting materials, making them more sustainable options than concrete and wood.
They also have a longer useful life of over 50 years, in addition to greater elasticity, insulation and atmospheric resistance.
Over the years, the majority of wooden sleepers have been replaced with concrete alternatives, but these are not suitable for all infrastructure types, and wooden sleepers still have to be used for metallic sections of infrastructure, tunnels with specific characteristics and certain deviations.
The Spanish rail infrastructure manager is now testing the synthetic sleeper as a new alternative, placing them on the Alcázar de San Juan-Cádiz line in the province of Jaén at the start of this year.
A total of 290 plastic sleepers, adding up to a length of 174 metres, were installed in sections of tunnel 10 and the metallic bridge over the Guarrizas river.
Adif has been inspecting the sleepers regularly and analysis has shown positive results.
