https://www.gerb.com/technical-insights
info@gerb.com

Vibration control of an IMAX® theatre

Since 1999, GERB spring elements have been ensuring an enjoyable cinema experience without disturbing noises from the outside.

With a weight of 5,000 tons, a diameter of around 44 m and a height of more than 25 m, the BFI IMAX® building in London makes its presence felt. More than two decades after first opening to the public, the cinema still has the largest screen in Great Britain, at 20 x 26 metres. The building was designed by architect Bryan Avery and has received a number of awards.
Located within a busy roundabout between Waterloo Station and Waterloo Bridge, with tunnels of the Waterloo and City Line passing less than 5 m beneath the building, and a number of other underground and mainline train tunnels and bridges in close proximity, the cinema is constantly exposed to vibrations. Neither cinemagoers nor architects nor structural engineers want these vibrations to be transmitted into the building.

Challenge

The major vibration source on the site are the tunnels of the Waterloo and City Underground line, running at a depth of less than 5 meters directly beneath the IMAX® cinema. The design team was faced with the challenge of how to eliminate vibrations from the trains running underneath the cinema to ensure a quiet atmosphere during movie performances.

Solution

An air gap was provided between the floor slab and the foundation piles in order to separate the vibration-loaded subsoil from the building. The construction floats on sixty-four huge anti-vibration spring elements, mounted on concrete pillars to control the level of structure-borne noise inside the theatre from passing underground trains. While vibrations from London Underground trains passing under the site could be easily detected in the ‚non-isolated‘ ground floor of the building, it proved very difficult to measure vibration from such events in the higher ‚isolated‘ part of the building.

Technical Facts:

Structure: Glass-clad circular steel
Vibration source: Subway lines 5 m below foundation level
Base isolation frequency: 3.5 Hz
Design load: 5,000 t

Result

When comparing the final vibration levels on the first floor to those in the ground on site before work began, a reduction of approximately 25 dB was achieved. This is consistent with the fact that with a background noise level of approximately NC 20 (Noise-Rating Curve) in the auditorium, no train events are audible at any time.

Share this post

Further Resources

You need further information on this topic?
Please do not hesitate to contact us with your individual question.
One of our project engineers will get back to you shortly.


    Vibration control of an IMAX® theatre

    Since 1999, GERB spring elements have been ensuring an enjoyable cinema experience without disturbing noises from the outside.
    With a weight of 5,000 tons, a diameter of around 44 m and a height of more than 25 m, the BFI IMAX® building in London makes its presence felt. More than two decades after first opening to the public, the cinema still has the largest screen in Great Britain, at 20 x 26 metres. The building was designed by architect Bryan Avery and has received a number of awards.
    Located within a busy roundabout between Waterloo Station and Waterloo Bridge, with tunnels of the Waterloo and City Line passing less than 5m beneath the building, and a number of other underground and mainline train tunnels and bridges in close proximity, the cinema is constantly exposed to vibrations. Neither cinemagoers nor architects nor structural engineers want these vibrations to be transmitted into the building.

    Vibration control of an IMAX® theatre

    Since 1999, GERB spring elements have been ensuring an enjoyable cinema experience without disturbing noises from the outside.
    With a weight of 5,000 tons, a diameter of around 44 m and a height of more than 25 m, the BFI IMAX® building in London makes its presence felt. More than two decades after first opening to the public, the cinema still has the largest screen in Great Britain, at 20 x 26 metres. The building was designed by architect Bryan Avery and has received a number of awards.
    Located within a busy roundabout between Waterloo Station and Waterloo Bridge, with tunnels of the Waterloo and City Line passing less than 5m beneath the building, and a number of other underground and mainline train tunnels and bridges in close proximity, the cinema is constantly exposed to vibrations. Neither cinemagoers nor architects nor structural engineers want these vibrations to be transmitted into the building.

    Challenge

    The major vibration source on the site are the tunnels of the Waterloo and City Underground line, running at a depth of less than 5 meters directly beneath the IMAX cinema. The design team was faced with the challenge of how to eliminate vibrations from the trains running underneath the cinema to ensure a quiet atmosphere during movie performances.

    Challenge

    The major vibration source on the site are the tunnels of the Waterloo and City Underground line, running at a depth of less than 5 meters directly beneath the IMAX® cinema. The design team was faced with the challenge of how to eliminate vibrations from the trains running underneath the cinema to ensure a quiet atmosphere during movie performances.

    Solution

    Technical Facts:

    Structure: Glass-clad circular steel
    Vibration source: Subway lines 5 m below foundation level
    Base isolation frequency: 3.5 Hz
    Design load: 5,000 t

    An air gap was provided between the floor slab and the foundation piles in order to separate the vibration-loaded subsoil from the building. The construction floats on sixty-four huge anti-vibration spring elements, mounted on concrete pillars to control the level of structure-borne noise inside the theatre from passing underground trains. While vibrations from London Underground trains passing under the site could be easily detected in the ‚non-isolated‘ ground floor of the building, it proved very difficult to measure vibration from such events in the higher ‚isolated‘ part of the building.

    Result

    When comparing the final vibration levels on the first floor to those in the ground on site before work began, a reduction of approximately 25 dB was achieved. This is consistent with the fact that with a background noise level of approximately NC 20 (Noise-Rating Curve) in the auditorium, no train events are audible at any time.

    Solution

    An air gap was provided between the floor slab and the foundation piles in order to separate the vibration-loaded subsoil from the building. The construction floats on sixty-four huge anti-vibration spring elements, mounted on concrete pillars to control the level of structure-borne noise inside the theatre from passing underground trains. While vibrations from London Underground trains passing under the site could be easily detected in the ‚non-isolated‘ ground floor of the building, it proved very difficult to measure vibration from such events in the higher ‚isolated‘ part of the building.

    Technical Facts:

    Structure: Glass-clad circular steel
    Vibration source: Subway lines 5 m below foundation level
    Base isolation frequency: 3.5 Hz
    Design load: 5,000 t

    Result

    An air gap was provided between the floor slab and the foundation piles in order to separate the vibration-loaded subsoil from the building. The construction floats on sixty-four huge anti-vibration spring elements, mounted on concrete pillars to control the level of structure-borne noise inside the theatre from passing underground trains. While vibrations from London Underground trains passing under the site could be easily detected in the ‚non-isolated‘ ground floor of the building, it proved very difficult to measure vibration from such events in the higher ‚isolated‘ part of the building.

    Share this post

    Share this post

    Further Resources

    You need further information on this topic?
    Please do not hesitate to contact us with your individual question.
    One of our project engineers will get back to you shortly.


      Further Resources

      You need further information on this topic?
      Please do not hesitate to contact us with your individual question.
      One of our project engineers will get back to you shortly.


        Scroll to Top
        Scroll to Top