By Lynda Myer
The installation process of bored piles on an excavation pit for a new commercial and office construction next to Munich’s central station in southern Germany, is undergoing by foundation engineering company Bauer Spezialtiefbau.
In April 2022, part of the Bauer Group, mobilized to the Bayerstraße 25 project site as the result of working for a joint venture between developers Ehret + Klein, Bauwens and Büschl, Bauer Spezialtiefbau.
In order to provide the digging shoring, Bauer is installing a total of 298 bored piles using the front-of-wall method, with low vibration, high precision dual-head drilling system.
With rotation in opposite directions simultaneously, the technique benefits two separate rotary heads for the continuous auger and the full casing.
According to Bauer Spezialtiefbau site manager Nicolai Gügel: “The bored piles reach down to a depth of 18m below ground and are being installed by a Bauer BG 30 with a diameter of 620mm. The excavation pit itself will be excavated to a depth of approximately 10.5m.”
Additionally, installing seven strand anchors in two layers, with some of them beneath the groundwater level, as well as bracing struts, will be up to Bauer.
Considering that three subway tunnels bore directly under the excavation pit and it could not be dug in one drive, for this project the level of the excavation pit was lowered by almost 1.5m and auxiliary shoring with sheet piles was also installed.
“The work area was therefore divided into sections, which are excavated in different phases and secured by girder shoring,” added Gügel.
November 2022 is the determined time for completing Bauer Spezialtiefbau’s works, while the full project is expected to be finished in January 2024.
