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I recently learned about spring mounts. These are used often in industrial equipment to reduce or eliminate vibration from the equipment like cooling towers, chillers, HVAC units, generators, pumps, and other types of equipment. Housed floor mounted spring isolators can have springs with up to 2" deflection. The bottom housing incorporates elastomeric ribbed rubber pad to prevent the vibration going downwards from the structure.

https://vibrasystems.com/spring-mounts.html

Here is a Z mount which is described as:

Z - Spring Mounts: 1" Deflection Z series mounts provide an excellent isolation from critical vibrations and efficiently protect structures from structure born vibrations.

Recommended for:

Air conditioning equipments, compressors, air handling units, centrifugal fans, pumps, chillers, and applications where low-frequency isolation is required.
Source: https://vibrasystems.com/z-spring-mounts.html

Considering it says "structure born(e) vibrations" (sic): "structure borne sound" is defined as:

Structure-borne sound results from an impact on, or a vibration against, a part of a building fabric resulting in sound being radiated from an adjacent vibrating surface. A typical example of structure-borne sound is footsteps on a floor which can be heard in a room below.
Source: https://www.designingbuildings.co.uk/wiki/Structure-borne_sound

So, the opposite of my intent, but could it work the other way around?

Here is an A1 mount:

A1 - Spring Vibration Isolators A1 series 100/140 mounts provide excellent isolation from critical vibrations and efficiently protect structures from transferring vibrations. Model A1-100 has 1 " deflection while model A1-140 has 2" deflection.

Recommended for:

Air conditioning equipment, compressors, air handling units, centrifugal fans, pumps, chillers, and applications where low-frequency isolation is required.
Source: https://vibrasystems.com/a1-1-and-2-deflection-spring-mounts.html

This one is to 'efficiently protect structures from transferring vibrations', seems similar to the Z mount, but could it work to protect the structure itself from vibrations being transmitted to it (originating outside the structure)?

I tried quality antivibration pads (multiple layers with rubber), and while they have some minor benefit, I still feel my bed shaking from a train about 0.8 miles away which wakes me up nearly every night. I also have a memory foam bed, so that does not help (it does in fact help over a spring mattress, but I still wake up).

I want to completely eliminate this vibration in the easiest way possible. The house and the ground are all obviously shaking. While I have done extensive research in soundproofing over the years and understand how to prevent sound and airborne vibration (from bulding a room within a room), I also need to eliminate the low-level shaking caused by the train.

The shaking is quite low. For nearly 2 years I did not realize it was the shaking of the train causing me to wake up. I have finally pinned down this as the cause. Before, I did not realize the vibration was even occurring, I though my heart was pounding from being awoken, but now I realize this shaking is actually the train, not my heart. Occasionally there will be a strong shake which I thought was a door slamming, but in fact it was the train shaking the floor.

What I don't know is if it works to isolate a structure from seismic activity - that is, I am calling the vibration from the train "seismic activity". I'm assuming it's a low level shaking, and need something that will eliminate this vibration. I plan to move in 1 year, but may not need to if I can solve this issue.

I am working on building a totally soundproof room, but now that I know the primary cause is this shaking, I need to be able to completely isolate a platform from this shaking. I can still build the soundproof room for total privacy, but it's in vain if I don't eliminate the shaking.

How can I eliminate this shaking (on my bed only or my soundproof room within a room only, NOT the entire house), and will these industrial spring mounts work? I'm willing to spend a few hundred for 4 of these mounts under the platform if it will solve the issue.

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  • So what are the formula relevant for this type of exercise?
    – Solar Mike
    Jun 7, 2020 at 19:13
  • Formula? I'm trying to eliminate train vibrations from my bed so I don't get woken up every night. This is real-life. I'm not a physicist.
    – diy user
    Jun 7, 2020 at 19:17
  • 1
  • I trust you know more about physics than me, and while I am reading this and appreciate this link, could you interpret it for me what you find to be relevant?
    – diy user
    Jun 7, 2020 at 19:22
  • 3
    How to make an airbag suspension. 1. Buy four basketballs. 2. Build four square boxes with bottoms, inside width is 1/2" larger than the basketball OD, height is 3/4 of basketball OD. Flip them upside down (open side down). Mount bed on boxes. Put basketballs under boxes. Inflate to suit. The box sides don't resist the air pressure, they just cage the basketball to keep it there. Jun 8, 2020 at 1:00

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You are spot on right. If there is shaking, and it is waking you up it, sound proofing your bedroom alone won't help. Sound proofing is about eliminating noise that can potentially come in from within your home (say a running television etc). It could involve

  • Having some kind of cone like structures on your walls that would prevent all echo
  • Putting easy to buy sound proof padding readily available on sites like amazon.
  • Double pane windows

But the above is likely not what you really need. To prevent the shaking you need do something to dampen the shaking. Now its not as simple as buying something off the shelf. The amount of shaking depends on how much your bed and yourself weigh. If you buy springs for the four legs that's too rigid, it will simply transfer the shaking. Buy springs that are too light will simply make the problem worse. I would recommend trying a few such springs first before committing. Yet another idea could be to attach small wheels and have it rest on a flat metal surface. This would cause the bed to move and not shake. Changing mattresses that has memory foam characteristics could also help. They are designed to not transfer motion. Here is a write up that talks about the same. Hope that helps and you get your bed shaking fixed.

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  • Thanks, but please be aware that foam/cone foam will do absolutely nothing to prevent sound from getting in. It only reduced echo inside the room. Soundproof padding will do nothing unless it is sealed airtight and has a lot of mass. You need to build an entire sealed room within the room to eliminate noise. Double pane windows will help (over single-pane), and triple pane is even better, but this option isn't possible for renters. My house does have double-pane. I do have a memory foam mattress as mentioned, but it does not eliminate the shaking, although it helps. Some motion is transferred.
    – diy user
    Jun 8, 2020 at 15:16

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