Noise and vibration management
[Title: Noise and vibration management]
[Vision: Two people in hi-vis vests setting up sound measurement equipment on a street corner with traffic around them. Close up of sound measuring equipment]
Sarah Alper – Technical Director Acoustics
Noise and vibration is a very personal thing and people react very, very differently to noise and vibration. We live in a city and cities are noisy places.
[Vision: Trams travelling down Swanston Street and people boarding them. Shot of the State Library of Victoria. Shot of a motorbike. Cut back to measuring sound on the street]
We are exposed to lots of noises within the city that we're used to and we don't tend to notice.
[Vision: Sarah measuring sound levels outside. Time lapse of tram traffic at an intersection. Shot of construction workers at Melbourne Metro geotechnical sites. Shots of trains passing ]
What we're looking at as part of the project is airborne noise, which comes from a specific source and we hear it at our ears.
We're also looking at vibration, which will travel through the ground and that's something that we feel. We're looking at noise and vibration associated with construction and we're also looking at noise and vibration associated with operation.
We're specifically looking at airborne noise related to the construction sites that will be at various locations, including the stations and some of the emergency access shafts.
[Vision: Animation of a Tunnel Boring Machine]
In the case of the tunnelling works, they will create vibration and it's heard as a low frequency rumble. And it's quite interesting because in Melbourne, we're quite used to ground borne noise because we've got a lot of tram movements.
[Vision: Aerial time lapse of CBD intersection. A moving tram is reflected on windows]
And if you think of when you're in a building, and the doors are closed, windows are closed but you can hear you can still hear the tram, and it's a low-frequency rumble. That's the sort of thing that we're talking about, when we're talking about ground borne noise.
[Vision: Construction site, pedestrians crossing the street]
Nadine Makin – Design Manager
For the most part, all our work will be underground and you will only really notice us when we come to surface at the stations or at the portals. So it's quite a minimal disruption compared to other methods.
[Sarah Alper speaking]
We're looking at an enormous number of sensitive receivers, residential locations, hospitals, hotels.
[Vision: Shots of trams passing outside RMIT, an apartment building, The Royal Melbourne Hospital, The Westin Hotel, a high rise building and Melbourne at night]
For areas where we have high rise buildings, and in particular where there may be evening or night time work, we've actually looked at implementing acoustic construction sheds.
[Vision: Animation of a construction shed, camera zooms inside]
They're going to be very big. They're going to allow trucks to enter them and for work to be undertaken within them.
[Vision: Sarah measuring sound levels outside]
Major infrastructure requires construction. There will be noise and vibration associated with it, but once that is complete we'll have a fabulous new rail line.