In the St. Alban-Graben in Basel, a busy street with two-lane streetcar traffic, a new underground parking lot is to be built, surrounded by the Museum of Art and Antiquities, the main branches of UBS and CS in Basel and the villas of the Basel "Daig". On 4 basement levels 350 vehicles shall find place.
In order to ensure that traffic on the surface is only obstructed by the construction work for as short a time as possible, the project engineers planned to carry out the work using the cover construction method. On the 150m long construction site, the overcut bored pile wall and the top concrete slab were first constructed to the south, while the traffic was moved to the north side. For reasons of space, the streetcar could only run in one lane in two-way traffic. After completion of the utility lines, the new streetcar route and the road construction, the construction activities in stage 2 switched to the north side and the traffic moved to the southern area.
When the surface was completed on both sides, the parking garage levels were started in cover construction. Three excavation openings allowed all the gravel material to be conveyed to the surface, loaded and discharged. At the same time, the parking ceilings were pulled in and the floor ramps were concreted. This was followed by all the interior work, installation of lighting and ventilation.
The completion of the parking and the handover to the client and the operator will mark the end of this extremely demanding construction project.
Services in detail
Excavation 30'000 m³
Bored piles 7500 m
Rill wall 450m2
Concrete work 5000 m³
Reinforcement 700 to
Pipelines 4 pipe blocks à 150 m
drainage 80m Ei-profile 1200/1800, 100m Ei-profile 1000/1500, 80m stoneware 500mm
Cover construction with 4 basements and overcut bored pile wall as excavation end. Inner-city civil engineering under streetcar and individual traffic.
Excavation, building stabilization, drainage, pipelines, dewatering, small drilled pile walls, underpinnings, excavation wall, concrete work, backfilling, road and pavement construction.
Inner-city conditions with streetcar traffic and high logistics requirements
Bored pile work with very tight space conditions between streetcar and buildings
Cover construction with 4 basement levels, excavation parallel to concrete work
Coordination with utility operators (IWB, Swisscom, Colt)
Tight schedule with several fixed intermediate dates
Construction interruptions and obstructions during archaeological research