LEC innovate to redefine Recouvrance Bridge, Brest, France

April 27, 2012
Date Announced: 27 Apr 2012 A pedestrian lighting integrated into the handrail.Form and function meet artistic application in difficult installation conditions to characterise this historic lift bridge.LEC innovate to redefine Recouvrance Bridge, Brest.The Recouvrance lift bridge is one of the longest and highest in Europe and has recently undergone modernisation to welcome a tram line as part of the development of Brest’s transport infrastructure. LEC collaborated with the Urban Community of Brest to provide a radical redesign of the lighting scheme on the bridge. By lighting the footpath using LED spotlights integrated into the handrail and illuminating the upper 44m of the four iconic 70m lift towers with artistic colour changing lightbars, the bridge now has a completely different identity at night.With very strict integration constraints, as well as photometric and aesthetic requirements the project needed a high quality of lighting for both applications. As such, LEC met the brief by deploying two original product innovations for the first time on this iconic site.The Handrail - School 5640Re-Imagining urban bridge lightingFor lighting the newly created pedestrian area, the local authority needed to integrate functional lighting into the handrail of this space. The LED solution from LEC provides safety, with a very low voltage solution (24 volts) whilst also reducing power consumption by 5. Furthermore, the lighting complies with all functional and disability standards by achieving an average uniform illumination level of 20 lux.Continuous, functional and precise lightLED spotlights with elliptical distribution lenses placed every 3.75m provide a smooth and uniform light output without any upward light loss, further enhancing cost-saving.Discreet and harmonious lightingThe small size of LEDs is a major asset for developing lighting solutions that were previously impossible. The LED lighting integrated into the handrail becomes an applicable, functional alternative to traditional solutions. The LEC product makes the subtle integration both visually discreet and imperceptible to the touch and is suitable for diameters from 42mm to 76mm, both implemented on this project.A Historical Bridge…The famous Recouvrance bridge of Brest overlooks the military port on the river Penfeld. It connects the left bank of the city to Recouvrance, one of the oldest parts of town. This iconic work of engineering replaced the Pont National swing bridge which was destroyed in Allied bombing in 1944.Opened in 1954, the present lift bridge is considered a protected heritage item and a major characteristic work of post-war reconstruction. Ligny 5635Form meets FunctionIn order to provide a restored, modernised and original bridge to the people of Brest, the Urban Community of Brest has chosen a solution offering dynamic lighting and colour, all the way up the outer sides of the lift bridge towers.The technical innovation suggested by LEC provides a result in line with the aesthetic expectations, coupled with a high luminous efficiency and a perfect integration with the architecture of the bridge.Visually & Econmically PowerfulTo fulfill the specification with traditional light sources would have been an incredibly difficult task so only an innovatively apdapted LED product could deliver the brief both qualitatively and economically. The use of red, green and blue LEDs provides a stunning artistic and flexible effect whilst maintaining high efficiency, unlike coloured filters which dramatically reduce the light output. In addition, a selection of high-performance lenses focus the LED and provide a precise and impactful “painting” of the 44m high bridge towers. This result also comes with a low energy consumption of just 300 watts per pier.Successful Architectural IntegrationThe LED source allowed LEC to design high power linear spotlights to continuously illuminate from the base of the tower. The colouring of the Recouvrance bridge towers is provided by diminutive 4.6m long lightbars, their compact design ensuring minimal visual impact of the installation itself.In addition, the design of LEC product incorporates connections for cable entry without intervention to the sealed LED housing. This allows the integration of any visible cable to provide a discrete solution.An iconic projectThe passage of trams across the bridge inspired the need to adapt the structure. The lifting bridge floor could not bear the weight of the new traffic flow. It was completely replaced and the “fixed spans” were reinforced. This construction site makes use of specialised professionals with divers and climbers working for several months on this bridge which will now become a promenade, shared between different travel methods.The new Recouvrance bridge will be inaugurated on June 23rd, ahead of the “20 years of Brest maritime festivals”. The “Les Tonnerres de Brest” festival takes place from July 13th to 19th.Interview with Hubert Le Sech,Street Lighting Manager, The Urban Community of Brest.“How and why did you choose LEC?During the renovation of the bridge we had decided to implement corbels to achieve a footpath on each side of the bridge, where only thin pavements existed before. At first, lighting this new area with bollards had been presented but the fear of vandalism led us to look at alternatives. At this point, LEC has proposed a functional application to be integrated directly into the handrail. This innovation seduced us immediately.This well protected lighting source allowed us to solve the issues of vandalism, whilst LED technology was perfectly relevant very relevant given the nature of lighting effect we wanted.Was the choice of LED’s obvious?The small size of LEDs when integrated into the handrail was the ideal solution for us. The buildings around the central square of Brest are brought to light by LED technology, so we already know its long term cost benefits. For several years, our community has been engaged in a process to reduce energy consumption in public lighting, so the choice of LED was applied to this project.What were the difficulties of this project?The footpath aims to let the users of the bridge admire the panorama from both sides; hence we needed a discreet lighting solution as alternative to traditional columns which are too bulky with the lift functionality of the bridge. In addition, continuous illumination was required to standardise and unite the new space. The perfect lighting integration solution was offered by LEC. By putting the source into the handrail, it also maintains the unique architecture of the bridge.How would you describe your collaboration with LEC?We can truly recommend their exemplary co-operation. We had many technical challenges with our desired solution and LEC had the expertise to find an application that met our expectations. Our many meetings with them were creative and practical. The important collaboration between LEC and the installation team for the handrail was also very successful.Interview with Christophe Cheron,AOA – Architect.“What were the particular challenges of this construction site?The renovation project was driven by the first tramline installed in Brest, but this crucial crossing point was not wide enough to make way to the tram.The strategic dimension was the major constraint of the project. The lift bridge is at the end of the Arsenal of Brest and is integral to the passage of military ships. The towers are in a military zone and the bridge mechanism simply cannot fail. We had to change the entire central portion without touching the charismatic towers, which were in good condition. These towers also serve as light signals in the city.How and why was the footpath created?We replaced the “H” section central span, so that the tram could pass between the two towers. The difficulty was that this then created a lack of space for the pedestrian and bicycle path. We therefore added to the outside of the uprights to create a more pleasant passageway which also forms a balcony overlooking the sea and the iconic Arsenal.This viewing platform is the urban dimension of the project complementing the functional military usage of the bridge.How did LEC help you illuminate this space?For the functional light, we wanted elegant and efficient lighting, without visual crowding or light pollution. LEC offered lighting integrated into the handrail which was both powerful and compact. As vandalism is a problem in Brest, it also required manufacturing in a robust material and LEC has met these strict requirements.Why did you choose LED lighting for the towers?The Recouvrance Bridge is an emblem; it has always been visible from a long distance in both day and night. The previous neon-based lighting was costly in terms of maintenance and far less visually effective.During the renovation we wanted to provide robust, functional and innovative lighting. LED lighting became the clear choice by its ease of maintenance, life expectancy, small size and its remarkable power. Furthermore, control of the light via accurate optics was a major benefit in achieving a uniform effect of illumination that ended at the exact top of the tower, to avoid light pollution.How has LEC added to the requirements of this emblematic work of engineering?LEC has developed a programmable multi- colour lighting system, which allows the creation of vastly different scenarios. This system lets us produce customise animations for events, such as the “Les Tonnerres Brest” sailing event,” which passes under the Recouvrance bridge. The bridge will now be the perfect viewing platform and add something unique to this event.

Contact
Heidi Pugniet-Boeck LEC Lyon +33 (0)437 483 100

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Web Site:www.lec.fr