Rehabilitation of the E17 motorway: Versatile Wirtgen technologies keep international freight traffic on the move
The Belgian city of Antwerp is the third-largest seaport in Europe with a total throughput in 2012 of 184 million tonnes and a major logistics hub for the shipping of goods between Europe and overseas destinations. To cope with the ever-increasing volumes of freight traffic, the world’s largest sea lock is currently being built in Antwerp.
High time for new roads
Of similar vital importance is the expansion of the road network: rehabilitation of the main traffic artery of the Belgian transport network, the heavily trafficked E17 motorway, was urgently necessary. The surface of this motorway connecting Antwerp with the French city of Lille via Gent still consisted of the original, old concrete surface dating back to the opening period in the mid-1970s.
Continuous longitudinal and transverse cracks, irregularities such as steps and tilting, concrete slabs that had drifted or settled over time, washed-out sealing compounds and reduced grip were among those indicators that were visible to the naked eye. It was obvious to all parties concerned: “in its current condition, the E17 was no longer able to cope with the tremendous, ever-increasing loads caused in particular by heavy-vehicle traffic.”
Special rehabilitation method with long-term advantages: CRCP
Rehabilitation of the first 11,6 km was to be carried out using a construction method that is specific to Belgium: CRCP (Continuously Reinforced Concrete Pavement) with a central concrete safety barrier.
Higher investment cost for CRCP caused by the continuous reinforcement are more than made up by the advantages: compared to standard construction methods, savings result from being able to dispense with joint production and maintenance; improved structural behavior enables the overall thickness of the concrete pavement to be reduced by 10% to 20%. “In addition, CRCP can be overlaid with a thin bituminous asphalt layer after 20 - 25 years - without cracks posing a problem”, explains Luc Rens, Managing Director at EUPAVE. This leads to significant increases in the overall service life.
Tight schedule favors Wirtgen Group equipment
An Area of 340,000 square metres needed to be rehabilitated in only six months. The authorities in charge therefore relied on the wide range of reliable, world-leading construction machines from the Wirtgen Group to complete this significant, large-scale construction project.
Wirtgen Large Milling Machines with 3,8-m wide, XXL-size milling drum units at work
Following removal of the existing concrete pavement, the W 2000 and W 2200 large milling machines from Wirtgen proved their high area performance when milling out the 25 cm of asphalt layer below - under ideal conditions, the W 2200 with its 3,8-m wide milling drum is capable of removing up to 1,200 tonnes of material per hour, which equals an incredible loading capacity of 60 trucks. Precise leveling while milling in a single pass combined with reliable material loading guaranteed quick proceedings finished in time.
The 3,8-m wide milling drum pay for themselves quickly through tremendous area performance levels as they enable wide road pavements to be removed in a single machine pass and the milled surfaces impress with perfect evenness. This reduces the number of adjacent cuts and turning manoeuvers required while at the same time driving down labor cost and thus offering a tremendous saving potential.
LEVEL PRO automatic leveling system
The large milling machines achieved the required evenness with the help of the Wirtgen automatic leveling system LEVEL PRO characterized by convenient, simple operation featuring the simultaneous display of parameters for both machine sides or the automatic adjustment of milling depth and slope. A great variety of sensors, such as wire-rope, cross slope or ultrasonic sensors can be integrated . Additionally, LEVEL PRO can be easily extended by the multiplex system or by laser or 3D leveling systems.
Paving the new asphalt course
In the next step, the new hydraulically bound base course was spread and compacted. Its evenness, bearing capacity, water and frost resistance combined into a stable foundation for the next operations steps on the E17 motorway.
The 5-cm thick asphalt separating layer serving as the base for reinforcement and concrete carriageway was paved to maximum precision by two road pavers from Vögele, SUPER 1900-2 and SUPER 2100-2, extremely powerful, high-performance pavers that enable even the largest construction projects to be completed quickly, precisely and with economic efficiency.
Thanks to their large material hoppers, they had sufficient mix on board even during truck changes. In addition, the NIVELTRONIC Plus® automatic leveling system ensured accurate paving true to line and level.
In full control with the ErgoPlus® operating concept
Easy operating was another advantage of the pavers being equipped with the user-friendly Vögele operating concept ErgoPlus®. The drivers’ operation console combines all function in logical groups, is therefore extremely clearly laid out and can be operated even when wearing gloves.
Paving mile after mile of safety with the SP 250
Safety was a top priority on the agenda for the new E17 motorway. To ensure maximum car and truck containment performance levels and thus prevent secondary accidents involving oncoming traffic, continuous concrete safety barriers measuring 0.9 m and 1.3 m in height were paved instead of using steel crash barriers. Their specific profile configuration safely contains any vehicles that collide with the barrier ensuring as well that they are bouncing back onto the road.
This is where the Wirtgen Slipform Paver SP 250 in offset configuration managed to play out its strength by completing an average 700 meters of high-quality concrete safety barrier per day. Exceptional flexibility is a hallmark of the SP 250 slipform paver with two front pivoting legs and two horizontally telescoping rear suspension units enabling full adjustment to any given paving situation. Additional advantages include numerous adjustment options of the belt conveyor and that moulds can be mounted on the left or right side of the machine. This enables transport trucks delivering fresh concrete to quickly pull into and out of the traffic passing along on adjacent lanes.
Paving concrete to perfection with the SP 850
For the most important part in this large-scale project, the paving of the concrete carriageway, paving to pinpoint precision, high compaction and optimal surface quality for a perfectly even concrete pavement were called for. After analyzing a number of different concepts, the company in charge of this phase of the project decided in favor of the Wirtgen SP 850 slipform paver.
Once a continuous longitudinal and transverse reinforcement consisting of ribbed steel had been laid on the asphalt pavement, the slipform paver SP 850 paved concrete slabs at a working width of 7.4 m and thickness of 25 cm, creating a surface of perfect quality to ensure optimal riding comfort with the help of its heavy-duty finishing beam and the super smoother.
The SP 850 was in operation non-stop to complete this mammoth job: three shifts, 24 hours each day, 7 days a week. The result. 291,000 square metres of perfectly even concrete carriageways meeting highest demands in terms of load-bearing capacity.
Unmatched Wirtgen Group service
In addition to placing high demand son machine technology, a project of this magnitude with an extremely tight schedule places equally high demands on technical service. Precisely that service is offered by the Wirtgen Group’s global network of subsidiaries and by well-trained service and process engineers.
Full service provided by the Wirtgen Group during the entire project guaranteed direct troubleshooting on site, quick delivery of spare parts and specialist support by highly qualified Wirtgen Group experts.