Inside the E04 Haga project (Haga Lot on the Gothenburg West Link rail tunnel project in Sweden). Is included the underpinning and construction of railway tunnel below the Skattehuset Building in Gothenburg.
The excavation by underpinning of the tunnel under the Skattehuset Building requires full control of the building deformations, interaction with the new supporting thick slab and detailed definition of the jacking/excavation phasing. Building and thick slab settlement control will be extended during all project phases until creep effect will be negligible. To correctly capture the elastic linear and non-linear long term interaction and settlements of the system building/slab, an overall model of the entire system is prepared. The model is simulated by means of SAP2000 and PLAXIS software that can account for non-linear and construction phase effects. Model includes the entire building structure with relevant weights, thick 3.5 m slab, micropiles, vertical and horizontal jacking system, intermediate steel structures. All construction phases are simulated including jacking at the various locations and existing micropiles cutting phases. Back-analysis of the system, different jacking sequences will be examined to minimize differential building settlements within specification limits. The same structural model will be used during the execution and successive jacking/control phases.
- Detailed Structural Design for all the phases of underpinning works including new supporting slab, micropils, building reinforcements.
- Detailed Structural Design for the portion of railway tunnel below the building
- Material and Construction specifications.