HERRENKNECHT TRIO MAKING GOOD ADVANCE ON BBT

摘要

Three Herrenknecht TBMs boring the Brenner Base Tunnel (BBT) continue to make good progress on the Italian construction lot 'Mauls 2-3'. One of the machines - a double shield 10.65m-diameter giant named Virginia - bored and lined 860m in March 2021, thereby setting a new monthly record at the jobsite. The average daily advance for March was 27.7m, and the daily best achieved was 36.75m. Running through the central eastern Alps, the BBT crosses a geology of quartzphyllite, shist, gneiss and granite located in the collision zone of the European and African tectonic plates. The overburden varies between 1,000m and 1,500m. Rock mass permeability in some places may need to be reduced by extensive grouting; environmental rulings prohibit lowering of the water table.