ACOUSTIC, NOISE AND VIBRATION
The highest sound pressure level of airborne noise on site is generated by
the train. To achieve lower noise level and higher safety for other mobility groups the
speed of the train on the distance of 570 meters (from the train station to existing un-
derground tunnel) is limited to 20 km/h when the maximum generated sound level is
80 dB. Presented table shows sound pressure level for the train on octaves.
Sound pressure level, dB
Frequency, Hz
Train at 20 km/h at15 m
63 125 250 500 1000 2000 4000 8000
81 88 80 76 72 73 69 65
dB
80
Table 1 Maximum sound pressure level on the site
According to the regulations on the allowable sound pressure level in housing
units maximum value is 40 dB from 7 AM till 11 PM and 30 dB between 11 PM and
7 AM. The table given below presents allowable sound pressure level on the same
frequency levels as for the train so that it is possible to make an average calculation on
required sound transmission loss of each building element.
Sound pressure level, dB
Frequency, Hz
500
1000
2000
63 125 250 Housing / day (7 AM - 11
PM) 63 52 45 39 35
Housing / night (11PM - 7
AM) 55 44 35 29 25
dB
4000 8000 32 30 28 40
22 20 18 30
Table 2 Required sound pressure level in housing units
In this project a simplified system of calculating the sound pressure level and
transmission loss was used, in which reflections of sound from surfaces outside and
inside the building are not taken into account. To meet regulation requirements the
level of noise inside apartments must be lower than presented in the table figures. This
means that higher values of transmission loss for each part of construction (window,
exterior wall, floor slab) improve sound insulation. Mentioned values should prefera-
bly be roughly equivalent to achieve better performance.
Today Estacio de Franca train and tram networks do not operate during the
night, although as the required sound pressure level in apartments during the night is
lower, the project provides calculations on required levels of the sound transmission
loss for the night time so that possible changes of the operation time will not disturb
residents.
Housing / night
63 125 Required transmission loss, dB
Frequency, Hz
250
500
1000
2000
4000
26 44 45
47
47
51
49
8000
dB
47
Table 3 Required transmission loss according to calculations
page 140
TRANSPORT & DOMICILE:
an architectural intervention to integrate transport infrastructure with housing for Barcelona.
Efimovich Alina