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Is GRP composite the answer to speeding up improvements to our rail network?

With glass-reinforced plastic (GRP) technology now a standard construction material in a variety of industries, is it time the rail industry took a fresh look at this versatile and durable composite? Stuart Burns, managing director of Dura Composites, explains why GRP offers significant improvements over traditional materials and is providing innovative and sustainable solutions for a range of key rail projects.

Whilst GRP has been used successfully since the 1930s in the manufacture of cars, trucks, boats and aircraft, the recognition of its benefits as a key construction material are somewhat more recent. Although traditional building materials such as wood, concrete and steel have proved enormously successful over the years, they do have a range of limitations – which recent innovations in GRP materials are now able to address.

Working with several key Network Rail contractors including Amco, Essex-based Dura Composites has supplied and manufactured bespoke GRP solutions for the rail industry in recent years, including anti-slip walkways for maintenance and wash areas, station platforms, tubular hand railing, signal box access structures and ballast retention systems.

Stefan Jastak, senior buyer at Amco Rail, described his experience of using GRP: “Efficient and sustainable solutions have always been at the core of our work for Network Rail. In choosing GRP from Dura Composites, we’ve been able to continue to innovate whilst delivering timely results that will last well into the future.

“We are always looking ahead and embracing new technologies that help us do more with less, and have found that the low weight and ease of use of GRP has significantly reduced possession times on major projects such as ballast retention systems, walkways and bridge refurbishments.

“Close collaboration and strong communication between Amco and the knowledgeable Dura team has been the key to success. For example, they provided our teams with hands-on trackside support during night shifts to ensure the whole team is adept at working with GRP. We look forward to working with the team on future projects.”

So how exactly is GRP composite technology speeding up improvements to the UK rail network? To answer this question fully, it’s important to look at the benefits and key limitations of traditional construction materials.

Concrete

Concrete is an extremely strong material, and performs well under compression, but its major drawback is its weight. Even small slabs can be difficult to manoeuvre or lift by hand, meaning that jobs such as fitting concrete trench covers often require heavy machinery, which can prove costly and take up lots of space. In addition, the difficulty of moving slabs in and out of position can also mean that maintenance and routine inspections are unnecessarily problematic. If a load limit is exceeded for any reason, concrete tends to crack, which causes safety issues and can even lead to site closures.

With GRP, these problems simply do not exist. GRP slabs of up to 100mm can usually be fitted without the need for any heavy machinery, and are also tested to support loads of up to 40 tonnes. The reason such a light material is able to provide such extraordinary strength is because of its engineered construction.

Rather than being solid GRP, the slabs are pultruded into a truss-like profile, resulting in a strong, and consistent final product weighing up to 80% less than steel and concrete alternatives. What’s more GRP has a ‘memory’, meaning that when GRP is loaded it deflects rather than cracks – and then returns to its original form.

Steel

Steel is one of the most-used materials in the industry, and is typically used where absolute strength is required. Although its performance in tension and under load is remarkable, it does still have a number of drawbacks. Firstly, steel, like concrete, is heavy and usually requires heavy lifting gear or significant manpower to manoeuvre steel parts into position. Secondly, steel is cold to the touch, especially in winter, which makes it less suitable for applications such as hand rails. Steel is also very slippery when wet, and even when combined with a chequer plate ‘anti-slip’ finish, there are often issues with lack of friction.

In recent years, GRP has been selected as a suitable alternative to steel to help address these issues. GRP composites are not only exceedingly strong, but are also far easier to manoeuvre, meaning that installation costs can be dramatically reduced. Unlike steel, it is also easy for composite products to be adapted to provide one of the highest anti-slip surface finishes ever tested .

In addition, items such as handrails made from GRP composite elements are far warmer to the touch during winter and reduce the risk of causing freeze burns in the workplace. The most significant advantage of GRP composite materials over steel however, is the ease with which they can be cut to size.

Although it is possible to cut steel to size on site, it requires special equipment and individuals trained in metalwork. Further, once steel has been cut, it should be re-galvanised, meaning that it needs to be transported off site and then back on again, costing valuable time and money.

Composite GRP materials, though tough, can be modified with ease on site using standard power tools, and don’t require extra treatments.

Wood

One of the oldest building materials still in existence, wood is attractive and can add warmth to virtually any space. Common industrial uses include flooring, decking and beams.

Although wood is versatile, it does require a great deal of maintenance to keep it looking good and prevent rot, mould, and splintering, especially when used in areas exposed to the elements.

Good quality exotic hardwoods command a premium price and even these require maintenance.

Composite products, on the other hand, have been carefully engineered to avoid these problems.

Aside from GRP, other new composite products to the market such as Wood Plastic Composite (WPC) is made from a mix of recycled plastics and reclaimed hardwood with various bespoke additives, and have a similar appealing appearance to natural wood.

WPC is also impervious to rot, mould and splintering and its unique composition means that it is not slippery, even when wet. What’s more, it requires virtually no maintenance to retain its impressive aesthetic.

This makes products such as composite cladding ideal for station refurbishments as they provide a natural wood appearance without the maintenance headaches.

So, whilst it’s clear that composite GRP offers major benefits over traditional materials in terms of strength, durability, manoeuvrability and cost – what are the specific properties that make it so suitable for applications in the rail environment?

Anti-slip

Transporting bulky, hazardous or heavy items from one place to another is common in most rail environments, so it’s important that any flooring used provides the maximum amount of grip. Not only can on-site falls be extremely dangerous, but they can also lead to expensive and time consuming litigation!

Concrete and metal surfaces can become very slippery when wet, but recent innovations in GRP have addressed this problem.

At Dura Composites for example, our GRP flooring products have angled quartz bonded to the top surface using resin, which produces a surface with an extremely high slip resistance.

When assessed under British Standard Test BS4592 (a test devised to determine the slip resistance of industrial flooring intended for use in wet areas), GRP flooring is over twice as effective as metal grating, and over three times more effective than chequer plate flooring.

Non-corrosive

When handling dangerous chemicals or corrosive liquids, it’s important to choose a floor capable of withstanding spillages and leaks, to avoid compromising the integrity of your flooring and the safety of workers and occupants.

GRP flooring systems are incredibly tough and can withstand contact with harsh chemicals.

Spark free

Historically, many rail environments have metal walkways and metal handrails. Where metal is present in work areas that are in constant use, there is a continual risk of sparking, which can be extremely dangerous. GRP can be used to replace metal grating, flooring slabs and hand rails and is specifically designed to avoid sparks no matter what it comes into contact with.

Mesh composition

Whilst a flat flooring surface may seem like the obvious choice for most projects, if a spillage occurs it can lead to pooling, which in turn can lead to accident and injury. GRP can be manufactured as an open mesh grating surface, which can be very useful if you require different levels of flooring, or if your flooring will come into contact with liquid that needs to drain through.

Hassle-free installation

Having the right fixings is crucial if your new flooring or handrailing system is to be a success. It’s important to provide your supplier with as much information as possible about the location of your flooring and how you want it to function before you get started.

At Dura Composites, we’ve spent the past 16 years coming up with a wide range of different fixing systems and accessories to make the installation process as simple and quick as possible.

For example, we now have a massive range of 316 stainless steel clips, clamps and panel-to-panel joiners that allow our GRP panels to be installed either permanently or temporarily.

Adjustable pedestals, made from a variety of durable composite materials, can also be used in situations where room is needed for cables and pipes to travel underneath a platform or walkway or to eliminate a change of height from one room to another.

With significant benefits over traditional materials, it’s clear that GRP is already proving its suitability for a wide range of rail applications.

Thanks to its strength, durability, ease of handling and affordability, it will continue to drive innovation across the rail industry – helping to ensure that solutions are both long-lasting and cost effective. 

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