Pandrol delivered a multifaceted track solution including fastenings, catenary and floating slab mats. The unique and challenging requirements led to Pandrol developing a new composite plastic baseplate, the SEE-SD. This baseplate is designed to be embedded into fresh concrete or by wet pour methods. This would be more cost effective than a traditional aluminium/steel casting and would be easier to handle and install on the track. The SEE-SD provides adequate resilience (stiffness) to attenuate to the concrete slab and provides large vertical adjustments to the rail position. The Pandrol air evacuation system prevents trapped air entering under the baseplate. The SEE-SD plastic baseplate has a special feature of vents and channels that optimise insertion into concrete and ensures excellent resistance to lateral forces.
Once the system was developed, Pandrol’s technical team carried out rigorous tests to demonstrate to the customer that their solution could meet both performance and cost requirements. This required technical validation of the system, including a complete and fully tested assessment of Pandrol’s recommended solution.
The SEE-SD assembly is designed to give a typical vertical dynamic stiffness of around 60 MN/m. It offers a wide range of pad stiffness levels, making it suitable for meeting noise and vibration mitigation requirements on this project. It also meets all requirements of the latest updates of EN 13146 and EN 13481-5 standards. In addition, its performance relating to electrical insulation complies
with EN 13146-5:2012.
The baseplates used in the SEE-SD design is made from glass fibre reinforced polyamide material in order to provide maximum resistance to lateral loads. The baseplate is not ‘laid’ on the concrete but ‘anchored’ and integrated into the slab. There is consequently no risk of slippage. The stress level in the screws is significantly reduced even on tight curves, as a result of the anchoring system, which is based on the use of two screws.
The SEE-SD was designed for use with the SD clip, with its screwed design that optimises track construction costs and provides very high technical performance. SD stands for ‘safely driven’ which relates to the controlled clip guidance from the ‘parked’ to the ‘in-service’ position.
SD insulated blocks are designed to offer lateral adjustment of the track gauge in increments of 1.25 mm. The method to adjust the gauge is managed simply by adapting the insulated block combination. SEE-SD meets the requirements for all urban rail networks, from tram lines
to modern light rail and high capacity metro applications.
Over the lifetime of the project Pandrol has manufactured more than 200,000 SEE-SD fastenings systems to the French rail consortium ETF and Colas Rail on behalf of Metro de Santiago.