Innovative Noise and Restraint Barrier
M1 Junction 39 is in the middle of a densely populated area with housing adjacent to the carriageway and slip roads. There have been complaints from residents over many years in relation to the noise, but funding has not been available for noise fencing until now.
Scheme background and modelling
The location was declared a noise impact area and funds were made available through the Environmental Designated Funds plan. Scheme modelling incorporated traffic volume and speeds, topography, deprivation, prevailing winds, customer benefits and experience.
Traditional and approved designs for noise barriers include a separate vehicle restraint system on its own foundations. However, this site presented several problems such as; very limited space, housing for services and communication equipment, topographical constraints and a weak geotechnical embankment that meant we had to look beyond traditional.
We shared the problem with our supply chain partners at one of our supply chain hubs where VeRSco offered to look at developing a solution collectively with us and our client Highways England.
VeRSco proposed an innovative combined dual-purpose structure serving both as a vehicle restraint system and environmental barrier with a single shared foundation and narrow footprint to solve the numerous problems.
The innovative single foundation combined barrier installation meant that we would not need to use piled foundations and that we would not need to relocate or protect the existing services.
The design was rigorously tested, complies with all current standards and is CE mark rated to containment L2 which is more than the normal N2 standard for verges. And in addition, it can be readily adapted to fit around street furniture and across bridges avoiding the gaps you would see in traditional barrier design.
Installation is made simple through precast reinforced concrete units designed to form continuous structurally sound foundation regardless of ground conditions and allowing installation during adverse weather meaning less time on site and much less construction noise. We have also made use of the closure to carry out additional maintenance work.
During the process we have been consulting with residents by a holding public engagement event, carrying out letter drops at different stages to update on progress, communicated 2 weekly progress updates to Parish council, site information boards and social media postings. We have also met with some customers and responded to enquiries. Outcomes from the consultation process included limiting vegetation clearance where possible and the choice of the leaf green colour on the reverse side of the barrier that faces customer properties.
And, modifications have been made to the installation process on site as the operations team propose improvements that will reduce green estate maintenance once the barrier is fully installed. This not only protects the barrier foundations but will reduce future costs of upkeep, demonstrating a wholly collaborative approach.
Once complete the barrier will also house steel crash doors to access emergency egress areas in the case of a breakdown, these exit areas will be lit by photo-voltaic motion powered solar lighting and clear signage and the residents will benefit from an estimated 37 decibel reduction in noise.
The original budget was set at £7.5 million plus around £1 million for additional vehicle restraint system replacement but the innovative combined system is costing around £5 million which is an estimated saving of 40% or just under £3.5 million in efficiency.
The new product has accepted to Highways England portfolio office as an efficiency lever. The scheme also has a carbon reducing Solartainer powered facilities, offers 24-hour working where traffic management permits, off site pre-cast construction benefits, managed motorway signage and solar powered lit positions of safety.
The total length of the pioneering combined noise and restraint barrier once fully installed will be approximately 2.1 kilometres. A-one+, Highways England and VeRSco are very proud of the solution they have collectively brought about. It delivers safety, efficiency and customer service and can be easily implemented elsewhere as demonstrated at our collaborative learning event held recently.