The modern mid-range hotel is located in the immediate vicinity of Berlin-Brandenburg Airport, just one S-Bahn stop from Terminal 1. The concept of the hotel brand is perfectly tailored to ‘business travellers with a packed schedule, as well as leisure travellers for whom every minute counts’. Spread over four upper floors and two basement levels, 271 rooms, a large lobby, restaurant and conference areas, as well as 193 parking spaces, will be created.
High groundwater level makes trough-shaped excavation necessary
27,000 m3 of soil had to be excavated to create the 3,900 m2 construction pit. The soil is cohesive down to a depth of five metres, followed by silty sands. Since the groundwater level is only a few metres below ground level, the six to seven-metre-deep construction pit is being built as a trough pit and kept dry until completion with the help of a residual water drainage system. A total of 3,820 m² of sheet pile wall will be constructed to enclose the excavation pit. The horizontal waterproofing of the excavation pit will be achieved by means of an injection gel base over an area of 3,900 m². The injection gel base is an ecological and economical waterproofing option against rising groundwater. The minimal use of cement reduces the CO2 footprint and the groundwater-compatible ingredients make it environmentally friendly. The sheet pile walls are braced with 30 tonnes of waling and tied back with 112 temporary grouted anchors between 18 and 20 metres long.
Full service ensures deadlines and quality of execution
As the hotel project is subsidised by the KfW development bank, adherence to deadlines and quality are of particular importance. ‘The fact that PORR realises construction projects efficiently and economically is largely due to our ability to offer all construction services from a single source. The close cooperation between building construction and special civil engineering accelerates the processes, avoids interface losses and increases both adherence to deadlines and the quality of execution,’ explains PORR Special Civil Engineering Regional Manager Patrick Günther.