Page 346 - 360.revista de Alta Velocidad - Nº 5

Sepúlveda Abad, Silvia. Lastra de la Rubia, Emilia.

• Double track tunnel instead of two single track tubes with the aim of presenting a larger
cross-section, only applicable in the project phase.
• Inclusion of connecting galleries between tubes, as long as the doors of the same are open
and thus act the galleries as fireplaces. It must be taken into account that this aspect should
not go against the safety regulations of evacuation in case of emergency (propagation of
smoke in case of fire).

• Inclusion of ventilation wells inside the tunnel near the portal area.

Figure 6. North Porous Portal. Perthus Tunnel.

Due to the great development of the Shinkansen over the years, a regulation has been considered
that limits the value of the micro-pressures to 20Pa in the vicinity of tunnels.

Until 2013, this was the only existing regulation regarding the sonic boom effect and was also
assumed by much of the world in the civil design of tunnels. In September 2013 a new German
standard introduced as a module of the already existing DB Ril 853 was presented at the 15th
International Symposium "Aerodynamics, Ventilation and Fire in Tunnels" which limits the value
of the decibels produced by the sonic boom. This limitation has two variants:
• In the vicinity of buildings, the decibels in C-weighting (evaluation of high sound level
sounds) are limited to the following values:

• Residential areas: 70dB (C).
• Parks and Gardens: 85dB (C).

• Industrial Zones: 95dB (C).

• On the other hand, in the case of non-proximity to the previous elements, the decibels are
limited to a distance of 25m from the portal to 115dB (C).

This regulation has been presented after carrying out a comparative study between actual
measurements and a numerical model in the Katzenberg tunnel (Karlsruhe - Basel line) of about
9.4km in length, bitube and single track. This comparative study is currently being used in the
analysis of the German high-speed rail network.

344 360.revista de alta velocidad