Interdisciplinary optimisation of injection methods in the construction lot H52 BBT

For the excavation of a hydrogeologically important section of the Brenner Base Tunnel (BBT), intensive injection works before excavation are necessary. The main objective of an interdisciplinary working group is to optimise these injections during the construction phase. The so‐called Hochstegen zone comprises two water‐bearing zones. The first zone, consisting of porous, metamorphic Triassic rocks, requires fine granular injection mediums, injections with maximum rates of 20 l/min and cementitious and chemical injection materials. The second zone, a water‐bearing zone in the Jurassic Hochstegen marble with micro‐karstic solution elements, requires a high volume injection method with maximum rates of approximately 500 l/min and an injection mortar with high density (2.3 t/m).