Eight-lane widening of the federal motorway A 1 and construction of a new Rhine bridge in Leverkusen

In 2012, it was discovered that the Leverkusen Rhine bridge, which dates back to the 1960s, had serious structural damage. The need to close the motorway to trucks weighing more than 3.5 tonnes on several occasions since 2013 due to the structural damage led to high economic and private losses.

At the beginning of 2013, Straßen.NRW invited four engineering firms specialising in large bridge construction to take part in a two-stage ideas competition. In this competition, the group led by the engineering firm GRASSL, in which KOCKS ENGINEERS are responsible for the roads, drainage design and the technical noise report, was able to prevail against strong competition.

The construction project to be planned comprises the new construction of the Rhine bridge and the expansion of the A 1 motorway and covers the area from the Cologne-Niehl junction (inclusive) to the Leverkusen-West motorway junction, including the so-called ‘elevated road A’. The section of the A 1 motorway will be widened to eight continuous lanes due to the forecast future traffic volumes. An additional manoeuvring lane in each direction will be provided between the Cologne-Niehl junction and the Leverkusen-West interchange. The ramp alignment at the Leverkusen-West motorway interchange will be adapted to the modified route of the A 1 motorway.

Intensive consultations were carried out with regard to the ability to obtain design permission and the feasibility of construction, including the proportionality of noise protection systems, construction procedures in the old landfill, replacement routes for pipelines, new and modified discharges into water bodies, flood protection and diversion routes for various construction phases.

For the design approval, the design documents were prepared, the synopses for the objections were drawn up, the one-week hearing was accompanied and the company was involved in the proceedings at the Federal Administrative Court in Leipzig.

Due to the project environment of the old Dhünnaue landfill, complex tasks had to be solved as part of the detailed design, including the execution of the foundation and the connection of the surface sealing of the old landfill to the new structures. In addition, the aspects of a sealing wall/barrier wall running in the vicinity of the A 59 motorway had to be taken into account in the design. The five basin facilities were designed according to the Guidelines for structural measures on roads in water protection areas (RiStWaG). One basin system is planned as a retention soil filter basin.

The urgency of the project required several specialist disciplines to work in parallel. BIM-orientated processing methods ensured efficient and effective information processing.