Level crossing surface systems need to provide a near seamless interface between the road and the railway, minimising any impact on susceptible users and vehicles such as disabled or infirm persons, bicycles, mobility scooters and children’s buggies. It is also important that anti-slip decking at footpath level crossings is provided.
Another essential requirement is illumination, so that users can safely use the crossing. This can be a problem, given the sheer number of footpath crossings on the network and their remoteness from power supply sources. Even if power and lights could be provided, the running and maintenance costs could be unsustainable, and lights may distract train drivers or neighbours.
A typically problematical foot crossing was Tangley, at Chilworth, near Shalford Junction in Surrey. The two entrances to the crossing are some way from the railway line. Users are faced with a steep set of steps, at the top of which they are immediately met with the railway line. To make matters worse, the crossing is not at 90 degrees to the line; instead, there is a slight skew. In poor light conditions, this may result in a user straying from the crossing onto the anti-trespass guards, increasing the risk of a fall in front of a train.
Network Rail, working with Strail, identified that the use of solar LED studs in the already-approved pedeSTRAIL crossing panels would provide a cost-effective risk reduction. Running along the edge of the crossing, these studs would guide users safely across in poor light conditions. With the LEDs powered by solar illumination, no power supply, cables or timers would be required – the panels would only need to be milled to suit the diameter and depth of the solar stud.
As Strail has supplied over 40,000 level crossings in 50 countries since the company was founded in Bavaria in 1976, it has the expertise and resources to develop such an innovative into a practical solution.
The fixation of the solar studs was a key topic during the design process for several reasons. Installation would need to be easily executed during production, making the solution cost effective, and removal/replacement on site would need to be simple but also vandal-resistant.
It was decided that the illumination colour would be blue, to avoid any conflict with signalling, and the light was designed to be visible to a crossing user while minimising any distraction to the driver of an approaching train. The system, which was trialled, evaluated and received product acceptance certificate PA05/06076 in 2014, was given the name pedeSOLAR.
High intensity LEDs provide up to 240 hours’ illumination and are visible at up to 900 metres. They only need a charge time of three hours at 100 klux (a typical sunny day), although any daylight will charge the battery.
The solar-harnessing free-energy technology and storage electronics are designed to maintain light outputs throughout a full annual cycle. The system is therefore sustainable and requires no maintenance, apart from possibly a clean now and again, and a battery change every eight years. The stud has a low profile, less than four millimetres above the footpath surface, and uses the same technology as ‘cats eye’ replacements for roads.
New moulded design
The main disadvantage of the original panel design was the time and cost it took to mill the holes into them. In addition, if they were to be installed onto the ends of an existing crossing, then the crossing would have to be extended by 900mm at each end as the original pedeSOLAR panels were 900mm long.
The product has now evolved and new moulds have been produced. The holes for the LED lights are now already moulded into the panels, removing the need to mill the holes at the factory and making the panels cheaper to produce. In addition, each 900mm panel can now be cut in half to produce two 450mm panels. Thus only one pedeSOLAR panel (2 x 450mm) needs to be purchased to fit on the ends of an existing crossing, reducing the material cost by 50 per cent.
The manufacturing process and materials used are unchanged from the previously approved system, so the surface and skid resistance remains the same, as does the specification of the LED studs.
A trial site for the installation of the new design pedeSOLAR panels was found at Hempstead Cutting No. 2 foot crossing in Uckfield, East Sussex.
The crossing itself was very poorly lit at night and its isolated location made it very difficult to run power to the crossing for lights. To make things worse, there were originally no crossing panels installed in the track so users had to cross over the rails and sleepers in almost pitch black!
The trial installation was a great success with very positive feedback. The 450mm panels were easy to install by hand, without the use of specialist tools – another advantage and cost saving.
The product has received full product approval and both full-depth and ‘universal’ panels are available. The latter can be re-used if there is a track renewal by adjusting the rubber packing underneath the crossing panels to suit the different sleeper profiles.
PedeSOLAR panels are sleeper spacing independent so there is no need to move sleepers prior to the installation.
Several systems have already been installed on footpath crossings and, given the level of risk reduction for the relatively small cost and installation resource involved, they should soon be a familiar sight all over the network.
This article was written by Paul Darlington.