Modern design and construction of tunnels, providing flexibility and safety- these are the main characteristics of the Austrian tunneling method. It is one of the most well-known and widely used technologies which we are presenting in our series devoted to the underground stations construction.
The New Austrian tunnelling method, a technique for modern design and construction of tunnels, is one of the methods used in the construction of the Sofia underground.
The new Austrian method was developed between 1957 and 1965 by the Austrian engineers Leopold Müller, Ladislaus von Rabcevich and Franz Pacher. In 1980, the Austrian National Committee for Underground Construction proposed an official definition: "The new Austrian method is a concept according to which rocks or soils around the workpiece cross-section become a load-bearing building element by activating a load-bearing rock (earth) ring". The main idea of the method is to artificially support the formation of a protective zone around the underground excavation and the conversion of the massif from a load-bearing to a carrier environment.
This is achieved through the use of deformable fasteners, which creates an opportunity for deformation of the underground workings. As a result of these deformations (of the order of millimeters) a redistribution of stresses in the array is obtained and the formation of a relief vault is supported.
According to the new Austrian method, a number of underground facilities were built - the meters in Vienna, Munich, Frankfurt, etc .; The Sheikan Tunnel (53 km), connecting the islands of Honshu and Hokkaido in Japan; the Channel Tunnel, passed through England, and others.
The new Austrian method was applied to the connection of the underground station at Vasil Levski Stadium and the tunnel under Dragan Tsankov Blvd. in front of the national radio. Due to the specifics of the geological conditions, the deep groundwater and the significant depth of the tunnels of the second underground diameter in the section under Cherni Vrah Blvd. from Hemus Hotel to J. Boucher Blvd., their construction was carried out according to the New Austrian Method. Subsequently, the tunnel to the next station on Line 2 - MS "Vitosha" was created with it, as well as some sites from Line 3 - the tunnel from the Small City Theatre "Zad kanala" to "Vladimir Vazov" Blvd. and part of the route in "Ovcha Kupel".
The team of BS Konstructia participates in the construction of the new lines of the Sofia underground. The metro stations "Boulevard Bulgaria", "Lomsko Shosse" and "Krasna Selo" are a highlighting part of our portfolio A team of nearly 100 professionals in the field of road and infrastructure construction were engaged in the implementation of projects. For the implementation of the project for Lomsko Shosse underground station, including a underground station, a 1250 m long overpass and two bridges, BS Konstructia won an award for "Project with the most significant contribution to the development of the urban environment" in the prestigious national competition Building of the Year in the year of 2012.