Eurailmag - #15 - March 2007 - (Page 98)

Tunnels Distance 40 m 1116 001-7 1116 001-7 Hermetically sealable doors Regulations and reference parameters The input parameters of the route meet Italian and Austrian regulations in force. In the absence of national regulations, EU regulations or analogue regulations from other states or networks were adopted (e.g. the DB 800.0110 regulation on route selection criteria). In addition, the Brenner Base Tunnel route meets the following regulations and/or basic input: • the TEN directives for newly-built routes with a projected speed of 250km/hr • railway traffic: in Austria trains travel on the right, whereas in Italy they travel on the left The change will take place in the vicinity of Innsbruck train station after the North entrance, and for trains to/from the Innsbruck bypass, through the connecting and base tunnels: • a maximum longitudinal gradient of 7% on the northern and 5% on the southern hill. The reduced maximum steady gradient reduces aerodynamic resistance in the tunnel. The minimum steady gradient of the southern hill was fixed at 5% to facilitate efflux of water, whose quantity is difficult to estimate during construction works (transitional effluxes) or during operating periods; • mixed traffic with a freight train/passenger train ratio of 80/20 • in addition, the planimetrical course of the route and location of the side accesses take into account other influencing factors, e.g., geomechanical and hydrological characteristics of rocks, environmental constraints, construction aspects, safety, ventilation and maintenance requirements during the operating period geotechnical data obtained and state-ofthe-art drilling technologies used. On the one hand, players must take advantage of any experience gained during similar projects, and on the other, use innovative working methods wherever possible. The construction methodology used is also influenced by the choice of construction phases. After having compared different scenarios, it was assumed that after obtaining the required authorisations, construction would be carried out in two phases: • construction phase one: preliminary works. Construction of the side access tunnels and of the intermediate headings, drilling the exploration tunnel located in the axis of the main tunnels • construction phase two: main works. Simultaneous construction of the main tunnels. The greater the preliminary research the less risks involved when constructing the main tunnels, which in turn influences the working methods used. When drilling the exploration tunnel, more information is collected on the characteristics of rocks and how they will behave during the tunnelling process. In doing so, risks related to the construction timetable and costs can be reduced. Stretches analyzed via the exploration tunnel may include unstable and problematic areas, from a geological point of view or involving the whole route. In any case, areas that are unstable and difficult must be studied in advance, via trial excavations. As regards methods for tunnelling the Brenner, there are two possible approaches: Brenner Base Tunnel – TBM tunnelling concept Construction Adopting the right construction approach is key when building a long base tunnel. It is mainly influenced by the geological and © BBT SE Issue 15 EURAILmag Business & Technology © BBT SE

Table of Contents for the Digital Edition of Eurailmag - #15 - March 2007

SOMMAIRE
NOTICE BOARD
COATINGS
NEWS
SERVICES
INFRASTRUCTURE
HIGH-SPEED LINES
TUNNELS
PEOPLE
ROLLING STOCK
WEBSITE DIRECTORY

Eurailmag - #15 - March 2007

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