Boehringer Ingelheim LSCC+QC

In 2017, Boehringer Ingelheim RCV GmbH & Co.KG began expanding its existing premises in Vienna’s Meidling district, adding a biopharmaceutical production plant covering 2.2 ha. This expansion project comprised a cell culture facility (LSCC Large-Scale Cell Culture) along with the necessary operations and logistics buildings. Totalling around €700 million, this project was the largest single investment a company had made in Vienna since construction of the General Motors factory in Aspern in 1979. The Specialist Civil Engineering department at PORR Bau GmbH was called on to apply their expertise in civil engineering aspects of the building complex.

A secure foundation

The commissioned work primarily comprised establishing a water-tight construction pit enclosure using diaphragm walls and secant pile walls up to 40m deep, implementing deep foundation elements up to 45m deep, all water management measures, all earthworks and creating the construction pit using the cut-and-cover method, including implementing the floor slab.

A major challenge

A special feature of this project is the fact that the Lainz Tunnel runs underneath the construction site. Given that the part of the production facility was constructed over the three tunnel tubes, the railway line operated by the Austrian Federal Railways (ÖBB) running from east to west had to be traversed while exerting almost zero loads. Prestressed reinforced concrete box girders were therefore installed, based in a secant pile wall in the watertight construction pit enclosure on one side, and a contiguous pile wall on the other side.

The ÖBB also issued precise specifications regarding the vibrations caused during diaphragm wall excavation. Given that site surveys conducted before construction identified very hard conglomerate layers in some areas, two different techniques were used to establish the construction pit enclosure in compliance with the specifications.

In the area close to the tunnel, the construction pit system was realised with a 40m-deep secant pile wall with a diameter of 120cm. Several piling rigs were used to compensate for the additional time required. In areas further away from the tunnels, the construction pit was secured with an up to 35m-deep diaphragm wall measuring 80cm thick. In addition to the construction pit enclosure comprising diaphragm and bored pile walls, more than 500 deep foundation elements were installed to depths up to 45m. As conventional anchoring systems were not possible with the Lainz Tunnel running through the site, the construction pit was established using the cut-and-cover method. In the installation of the steel auxiliary supports for the construction pit, PORR impressed with an innovative proprietary development that combined time efficiency and sufficient positional and depth accuracy

The groundwater control measures, with ongoing monitoring of water levels inside and outside the construction pit, comprised around 20 sampling and absorbing wells as well as a control gauge. In addition to lowering the groundwater, this also involved depressurising groundwater horizons under artesian pressure at depths in excess of 25m below ground level.

An outstanding achievement

The new plant was scheduled to be used to produce pharmaceutical products with cell cultures from 2021, so the construction schedule was exceptionally tight. However, thanks to its extensive portfolio and excellent cooperation between different departments, PORR was able to offer a solution to this extremely complex challenge within a very short period of time, providing everything from a single source. In addition to deploying a considerable number of employees, PORR also used six piling rigs and five cable excavators – a uniquely high concentration of specialist civil engineering equipment on one site. All work was completed on schedule, meaning that 2021 went down as a milestone year in the history of Boehringer-Ingelheim.