A5

The A5 highway infrastructure improvements near Hinckley, Leicestershire, had originally specified a concrete system to provide surface water drainage for the busy highway, as part of wider improvement works.

Having successfully used plastic piping systems for previous large scale projects, main contractor Galliford Try tasked Polypipe CGU with providing an appropriate alternative solution that would meet the demands of the project, but would also prove quicker, safer and easier for contracting teams to install beside the busy highway.

Utilising the popular Ridgistorm-XL piping system, Polypipe CGU’s design team engineered a solution to match the original 750mm diameter pipe specified to incorporate a single pipe run to sit beneath the road’s verge, complemented by two separate twin runs, with a combined length of more than 400 metres.

Polypipe CGU provided structural calculations and assisted the consultant engineer, Milestone, in engineering a reduction in the pipe stiffness from the original specification. This was accepted for use, allowing the works to commence as scheduled.

With Ridgistorm-XL being up to 94% lighter in weight than alternative concrete products, it’s easier to handle and reduces the need for heavy plant machinery, providing a number of benefits, including reduced installation time and cost.

The installation time was reduced further still by Polypipe CGU supplying Ridgistorm-XL in six metre lengths with ring seal joints, limiting the number of joints required and ensuring that each jointing process was as quick as possible – a vital consideration within a live highways environment.

The pipes were engineered to the exact strength required to meet the ground conditions and installation parameter – in this case, stiffness classes 2.67kN/m², 3.056kN/m² - allowing pipe to withstand external loading during the installation process.

Joe Scurrah, Site Engineer at Galliford Try, said: “With Ridgistorm-XL being able to be manufactured to the minimum stiffness classifications required to suit the site-specific ground and loading conditions, Polypipe CGU were able to offer cost savings compared with equivalent concrete systems.

“This also enabled the project to benefit from increased constructability, namely storage on site, speed of the installation and added health and safety benefits of using a plastic piping system.”

Emma Nicholls, Marketing Manager at Polypipe CGU, said: “We are increasingly seeing contractors and installation teams switching from alternative materials in favour of plastic piping systems, particularly in highways applications. In this instance, our team was able to provide a system that will help to keep a vital regional road network operational in all weather conditions.”

The project, due for completion in November 2014, also included a holistic range of highways solutions from Polypipe CGU – including three Stormcheck flow control chambers, the popular Ridgidrain surface water drainage system in sizes 100mm to 600mm, Ridgistorm-XL saddles for the connection of Ridgidrain to the Ridgistorm-XL pipe system, Type 8 Linflex land drainage in sizes 100mm to 160mm, and R.