The Wallstraßenbrücke replacement project in Ulm demonstrates how Liebherr tower cranes manage precision lifting in one of Germany's most constrained urban infrastructure sites. Seven tower cranes from Nagel Mietservice GmbH currently handle formwork, rebar cages, and concrete elements across 14 active rail tracks and a heavily trafficked federal road carrying up to 86,000 vehicles daily in the north-south corridor. The crane fleet centres on two Liebherr 520 EC-B 20 Fibre flat-top slewing cranes, which began operations in March 2026 and exploit fibre-rope technology to boost load capacity by 40 percent over conventional steel-rope equivalents.

What Technical Demands Does the Wallstraßenbrücke Replacement Impose?

The original Wallstraßenbrücke, completed between 1967 and 1969, carries the B10 federal highway over Kienlesbergstraße and adjacent railway infrastructure. Condition assessments concluded the structure requires complete replacement. The new bridge will span 187 metres and be built in two phases: the western half between 2026 and 2027, followed by the eastern section from late 2027 to early 2029, with final traffic release scheduled for summer 2029. The joint venture ARGE B10—comprising Matthäus Schmid Bauunternehmung GmbH & Co. KG from Baltringen and LEONHARD WEISS GmbH & Co. KG from Göppingen—leads the project and partnered with Nagel Mietservice GmbH from Ulm for crane and logistics planning.

The site's geometry presents two core challenges for crane operations: active railway operations below and continuous road traffic alongside the work zone. Formwork segments and rebar baskets must be positioned between tracks with millimetre precision. Modern assistance and safety systems fitted to the deployed cranes support reliable and efficient operation under these complex conditions, according to the manufacturer's press release.

How Do the Two 520 EC-B 20 Fibre Cranes Divide Duties?

On 12 March 2026 Nagel Technik Service erected the first Liebherr 520 EC-B 20 Fibre on site. This flat-top slewing crane operates with 80-metre radius and 52-metre hook height, delivering a maximum capacity of 20 tonnes. Its long reach covers the entire main work area and handles the heaviest single lifts, including formwork assemblies and rebar cages positioned between active tracks.

A second 520 EC-B 20 Fibre followed on 16 March 2026 on the opposite side of the site. Configured with 60-metre radius and 35-metre hook height, it accelerates cycle times and material turnover in denser working zones. Together, both cranes ensure full-area coverage with optimised load distribution.

What Advantages Does Fibre-Rope Technology Deliver?

Both 520 EC-B 20 Fibre units employ Liebherr's fibre-rope system, which substitutes high-performance synthetic-fibre ropes for traditional steel wire ropes. Key operational benefits include:

  • 40 percent higher load capacity using existing crane components, thanks to significantly lower rope self-weight
  • Improved handling and reduced maintenance effort compared to steel ropes
  • 14-year rope service life under normal operating conditions
  • On-site repair capability for up to 80 percent of rope damage incidents, avoiding costly and time-consuming rope replacement

The modular EC-B construction-kit system allows project-specific configuration of tower height, jib length, and load-chart characteristics, enabling precise matching to site geometry and lift requirements.

Which Support Cranes Complete the Fleet?

Beyond the two main slewing cranes, Nagel Mietservice deployed five additional Liebherr units to cover material distribution, perimeter supply, and fine logistics within the site:

  • One saddle-jib crane Liebherr 81 K at Blaubeurer Tor handles material distribution, logistic support tasks, and supply to peripheral zones. This bottom-slewing design delivers short set-up times and efficient operation for smaller loads.
  • One flat-top slewing crane Liebherr 202 EC-B, added from 17 April 2026, takes over lifting tasks in formwork and rebar construction.
  • Three saddle-jib cranes Liebherr 81 K and 81 K.1, operated by ARGE partner LEONHARD WEISS, are configured for high-throughput handling in confined spaces and cover fine logistics within the construction site.

The combination of high-capacity slewing cranes and flexible saddle-jib units forms a coordinated crane ensemble that efficiently covers both heavy single lifts and rapid material cycles in close-proximity work zones.

How Do Operators Achieve Millimetre Precision Between Live Tracks?

The site location between active rail and road traffic corridors imposes exceptional demands on precision, load capacity, and safety protocols. The B10 carries up to 86,000 vehicles daily in the north-south direction, and the construction zone spans 14 rail tracks. Inserting formwork sections between tracks and placing rebar cages demand millimetre-accurate hoist movements. Modern assistance and safety systems fitted to the deployed cranes support reliable and efficient crane operation even under these complex conditions, the manufacturer states.

For fleet managers and site planners evaluating crane solutions for constrained urban infrastructure projects, the Ulm deployment illustrates the practical value of modular tower-crane systems combined with fibre-rope technology. The 40-percent capacity increase over steel-rope equivalents translates directly into fewer crane moves, shorter cycle times, and reduced idle periods—critical factors when working windows are limited by rail and road traffic schedules.

What Lessons Can Contractors Draw from the Crane Concept?

The close collaboration between ARGE B10 and Nagel Mietservice during the planning phase enabled a tailored crane-and-logistics concept that addresses site-specific constraints. Nagel Mietservice provides project supervision, technical design, and flexible crane-equipment provision for partner Matthäus Schmid. This integrated approach—common among established rental-service providers—allows contractors to match crane capacity, reach, and hook height precisely to phased construction schedules without over-specifying equipment or accepting capacity gaps.

For operators working on bridge-replacement or railway-adjacent projects, the Wallstraßenbrücke case underscores the importance of early crane-supplier involvement. When site geometry, traffic management, and lift weights are mapped during tender preparation, rental partners can propose optimised fleet mixes that balance initial mobilisation cost against daily productivity and safety margins.

Further insights into tower-crane technology and project planning for urban infrastructure can be found in our coverage of mobile tower cranes versus telescopic cranes. Readers interested in Liebherr's broader equipment portfolio may also consult our report on the company's €2.5 million test facility for autonomous tracked excavators and our analysis of the R 9600 ultra-class excavator delivery to Northern Star Resources.

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