Munich, 27 June 2025 – Special civil engineering is considered the foundation of every demanding construction project. Only with sound expertise and precise execution can safe subsoil be developed economically. In Germany, PORR has positioned itself strongly through the acquisition of Stump Spezialtiefbau and Franki Grundbau in 2013 and 2017. The subsequent merger to form the current PORR Spezialtiefbau GmbH, headquartered in Munich and with further locations in Berlin, Chemnitz, Düsseldorf, Frankfurt am Main, Hanover, Oldenburg, Seevetal and Stuttgart, established the company as a technology leader in special civil engineering.
The broad range of services includes consulting, planning and implementation of complex foundations, construction pits, sealing slabs and soil improvement. PORR is also prequalified for all special civil engineering services for Deutsche Bahn and was the first company in the industry to be awarded the DGNB basic certificate ‘Sustainable Construction Site Special Civil Engineering’. This special award from the German Sustainable Building Council (DGNB) confirms PORR's outstanding commitment to sustainable construction and the responsible use of resources.
To improve the sustainability of a construction site, clients can opt for low-emission pile foundations or environmentally-friendly subsoil improvements, among other things. It is also possible to use recycled materials or environmentally-friendly processes when constructing cut-off walls. The experts support their clients right from the start if they are aiming for a sustainability certificate for their construction site.
Construction work close to water: DGNB certified
A particularly challenging project in the field of special civil engineering was the deepening of the harbour basin in Straubing, Bavaria (Sand district). The contract included the reinforcement of the existing sheet pile walls, where 1,076 permanent grouted anchors compensated for the increased static load caused by the deepening. In order to minimise disruption to port operations, the work was carried out exclusively from a 42 x 12 metre work pontoon. Particular challenges arose in terms of environmental protection and nature conservation: no substances were allowed to enter the Danube water, and noisy work had to be completed by the start of the breeding season on 1 March 2023, as parts of the port area are located in a bird sanctuary. The DGNB awarded PORR the ‘Sustainable Construction Site – Special Civil Engineering’ certificate for its exemplary construction site organisation and resource conservation.
Complex construction pits in Hamburg-Rothenburgsort
In Hamburg-Rothenburgsort, PORR was awarded the contract to construct an approx. 14,200 m² watertight construction pit for a major new construction project for the city. Around 1,000 apartments will be built here.
In addition to the foundations, the special civil engineering work included the installation of 10,620 m² of cut-off walls, 1,845 m² of diaphragm walls, 14,200 m² of soft gel base, 3,320 m of temporary strand anchors and 1,214 Atlas TMV piles. A particular challenge was to construct the continuous soft gel base of this size while simultaneously erecting the shoring walls – and all this within a tight schedule. In addition, the massive, unknown old buildings in the subsoil placed increased demands on the team and required a high degree of flexibility.
Diverse reference projects
PORR Spezialtiefbau can point to a long list of references for a wide variety of structures.
These include contracts such as the rehabilitation and cleaning of the Kerspetalsperre dam, whose listed dam wall covers an area of approx. 2,800 m², as well as roads, bridges, mountain railway stations, slope stabilisation, tunnels, power lines and wind turbines. These structures all have one thing in common: regardless of the soil conditions, they must have a stable and secure footing.
Conclusion and outlook
Sustainable construction methods are becoming increasingly important. Special civil engineering is indispensable for modern construction projects. PORR Spezialtiefbau GmbH has established itself as a leader thanks to its technical expertise and commitment to sustainability. With innovative, well thought-out solutions and a wide range of services, it implements demanding construction projects safely and efficiently.
