Building Isolation

Building Isolation Materials On Site

As space becomes a premium, the likelihood of a building being erected close to a source of vibration is greatly increased. Railway lines, both above and below ground, and busy main roads, particularly where heavy goods vehicles are active, can generate vibrations which can, over time, cause serious damage to a building.
Building isolation solutions protect a building’s support structures from ground-borne vibration. Similarly, building containing machinery which generates vibration must be treated to prevent those vibrations from spreading within the building or outwards towards neighbouring structures.
CMS AV have extensive experience in the area building isolation, from isolating a 540 ton printing press as part of North Wales Newspapers’ £16 million development of their new production site in Deeside, to preventing train-generated, ground-borne vibrations from entering into the main building structure of Paddington Central.
We take a fact-based approach, analysing extensive data to create a solution that is perfectly suited to the requirements of each vibration isolation project.
Brent Knox of Eric Wright Construction, the main contractor for the North Wales Newspaper project, said: “By recommending and delivering the right materials, CMS Vibrations was able to meet our exact requirements. Even under very tight timescales they ensured the project stayed on schedule by getting the products on site exactly when we needed them.”
The idea that to isolate a structure from the effects of vibration you simply have to put a layer of rubber beneath it is misleading to say the least. Similarly, it isn’t just a case of using a thicker layer of rubber the greater the amount of vibration experienced.
The most important characteristic of any vibration is its frequency. Measured in Hz, frequency is defined as ‘the number of oscillations per unit time’.
Just as the ‘problem vibration’ has a frequency, so too does the material used to combat that vibration. Known as the ‘natural frequency’ of the material, this is a function of the stiffness of the material and the mass that the material needs to support. The interaction between the problem frequency and the natural frequency produces unique results. One size certainly doesn’t fit all, and it is essential to seek the guidance of vibrations specialists such as CMS AV. Using a material with the wrong natural frequency can not only fail to solve the problem, it can actual make it worse by amplifying the vibration.
CMS AV produce a wide range of materials, each with their own natural frequency and load bearing capability. Our Regufoam vibration isolation material has a natural frequency ranging from 8 to 10 Hz and a load bearing performance from 0.01 to 0.4 N/mm2. Our RAV product has a natural frequency ranging from 10 to 12 Hz and a load bearing performance from 0.5 to 1.5 N/mm2.
For assistance selecting a vibration isolation material for your project, or just for some technical advice, call our experts on 02380 625568.
Client: North Wales Newspapers
Contractor: Eric Wright Construction
Vibration consultant: A W Irwin Associates
Foundation size: 28.25m x 5.5m x 2.0m deep

In brief
To reduce the impact of vibration and noise at a new North Wales Newspapers production site in Deeside, a range of Regupol RAV materials were used to isolate the foundation of a KBA Commander Press line.
Project scope
When developing its new £16 million production site in Deeside, North Wales Newspapers had to ensure that provision was made for the vibrations which would be generated by an active KBA Commander Press. To determine the correct vibration specification a review of the machine’s response frequencies and modal forms was undertaken.
To avoid resonance the bearing natural frequency had to be between8-10Hz and both the base and side walls of the press foundation had to be fully isolated. This was to prevent external vibrations from causing quality problems for the printing press and stop press generated vibrations from entering the building structure.
The construction phases involved the pit and isolated foundation block, with a 4.3m high concrete press table cast on top to provide support for the 540 ton KBA Press. To minimise problems for the paper loading system, it was deemed critical for the table and foundation block to be level within 2mm of the surrounding floor areas, which made material creep a primary consideration.
Results
CMS Vibrations met the criteria by identifying and installing a range of high performing Regupol RAV anti-vibration materials.
On the base of the foundation, 155m2 of Regupol RAV200 was installed with separate Regupol RAV400 bearings inlayed into the RAV200, both at a thickness of 60mm.
This system was designed specifically to withstand the heavy loads, deliver effective isolation and at the same time minimise long term creep.
For the foundation sidewalls, 69 linear metres of Regupol RAV300 was installed in 50mm thick bearing strips. The material was placed around the collar of the foundation to a depth of 500mm, between the floor slab and foundation block.
Benefits
• Excellent dampening and isolation characteristics
• High load bearing capabilities
• Environmentally friendly and fully recyclable
• Quick and easy to install
• Cost effective
• Minimal creep
• Independently tested by the Institute of Structural Dynamics at the
Technical University of Dresden, Germany

Our Building Isolation Products

 

Regufoam

Regufoam Vibration Isolation Material

  • Load Range 0.010-0.4N/mm2
  • Natural Frequency 8-10Hz
  • Polyurethane Foam
  • Designed to be Flexible
Regupol RAV

RAV Vibration Isolation Material

  • Load Range 0.05-1.5N/mm2
  • Natural Frequency 10-12Hz
  • Polyurethane-Bound Rubber Granulate
  • Fully Recyclable