Can sound travel through clay?

[Housey210]

TL;DR Summary

noise / vibrations impacting on my home and well being

HI,

Just found this on google "Can sound travel through clay?" and signed up.

2019 my home was hit by an energy wave causing a humming inside, no noise outside just in. the humming is 24 / 7 and worse in the early hours, 1am through to 6am. I am the only household suffering, it is so distressing with loss of sleep.
I am 70 mtrs away from a data server hub unit, serving the town with the internet. I know these data server hubs have become a big issue in the states.
this week I have found a dead 6 inch clay pipe in my garden connected to the main live 9 inch sewer that runs within 3mtrs alongside that data hub. The dead end in my garden is about 2mtrs from back of the house and has a concrete bung. My theory is the vibrations from the servers is travelling along the pipe, hitting the dead capped end and resonating in my home. The capped end is about 1mtr away from my live 4 inch sewer. Will vibrations travel in pipe void and in clay material? Two surveys, at my cost, links that building with 80-92hz, ground bourne. Thanks for any input.

 

[Dale]

Yes, clay can conduct sound, and a clay pipe can both conduct sound and resonate.

You might check with your local town government regarding noise ordinances.

 

[Baluncore]

What is the exact frequency of the hum?

Look for the power transformer. An overloaded power transformer will hum at twice the frequency of the mains power. That is due to magnetostriction in the transformer laminations.

Pole mounted transformers can efficiently couple vibration into the ground through the support poles.

The speed of sound is slow in clay soils or swamp, so the amplitude of ground motion is greater than in faster and deeper rocks.

Is there a big electric motor/generator running nearby? Heavy flywheels are sometimes used to provide continuous power to servers when there is an unreliable power grid.

https://en.wikipedia.org/wiki/Electromagnetically_induced_acoustic_noise

 

[A.T.]

Look for the power transformer. An overloaded power transformer will hum at twice the frequency of the mains power. That is due to magnetostriction in the transformer laminations.

Electric cars at the charging station can make humming noises. But usually not 24/7, only when a car is charging.

 

[russ_watters]

2019 my home was hit by an energy wave causing a humming inside, no noise outside just in. the humming is 24 / 7 and worse in the early hours, 1am through to 6am. I am the only household suffering, it is so distressing with loss of sleep.
I am 70 mtrs away from a data server hub unit, serving the town with the internet. I know these data server hubs have become a big issue in the states.

If you haven't already, download a "spectrum analyzer" app for your phone. I've played with a few and use SpectralPro most.

I have been plagued by a humming noise in bed as well. It was pretty soft, but it was clear and being the only sound I could hear, my brain locked-on to it, making it hard to sleep. I identified the frequency, then traced it with the app to a small manufacturing plant a quarter mile or so from my house; an exhaust fan on the roof.

Being worst at night is telling: if it is not very loud, those are the hours when there is the least background noise and wind to mask the sound. It may not be louder, the background noise is just quieter in those hours. A spectrum analyzer will be able to cut through the background noise and detect the sound outside so you can trace it back to the source. A "data server hub unit" sounds like a likely candidate. I don't know what it means, but I'd expect it to have an exhaust fan.

Options for mitigation: talk to the owner/operator. Upgrade your windows. Try a white noise generator when you sleep to drown it out.

Two surveys, at my cost, links that building with 80-92hz, ground bourne.

What does that mean? Is that the frequency of the sound? How was it measured? It seems way too low to be described as a "hum". What is the "link"?

 

[Baluncore]

I would expect a local source of noise, probably from a shaded pole motor, driving the fan in something like a domestic reverse cycle water heater.

 

[Housey210]

If you haven't already, download a "spectrum analyzer" app for your phone. I've played with a few and use SpectralPro most.

I have been plagued by a humming noise in bed as well. It was pretty soft, but it was clear and being the only sound I could hear, my brain locked-on to it, making it hard to sleep. I identified the frequency, then traced it with the app to a small manufacturing plant a quarter mile or so from my house; an exhaust fan on the roof.

Being worst at night is telling: if it is not very loud, those are the hours when there is the least background noise and wind to mask the sound. It may not be louder, the background noise is just quieter in those hours. A spectrum analyzer will be able to cut through the background noise and detect the sound outside so you can trace it back to the source. A "data server hub unit" sounds like a likely candidate. I don't know what it means, but I'd expect it to have an exhaust fan.

Options for mitigation: talk to the owner/operator. Upgrade your windows. Try a white noise generator when you sleep to drown it out.

What does that mean? Is that the frequency of the sound? How was it measured? It seems way too low to be described as a "hum". What is the "link"?

Hi , thanks for reply. The two noise specialists used FFT spectrum analyzer and found perfect frequency match of that in my home to the data server hub, which supplies the town with the internet. Low frequency is according to BS4142 is under 200hz.

 

[Housey210]

Yes, clay can conduct sound, and a clay pipe can both conduct sound and resonate.

You might check with your local town government regarding noise ordinances.

hi and thanks, from the info given just walked up to the data hub and placing ear to wall a very low hum, no noise. I am convinced this is resonance, vibrations form the many data servers in that building tranfering into the ground, the 9 inch clay pipe and travelling along, amplifying at the pipe into my garden.

 

[Baluncore]

hi and thanks, from the info given just walked up to the data hub and placing ear to wall a very low hum, no noise.

Your use of the technical language requires some explanation. How can a hum not be a noise? What do you mean by a hum? What do you mean by a noise?

I am convinced this is resonance, vibrations form the many data servers in that building tranfering into the ground, the 9 inch clay pipe and travelling along, amplifying at the pipe into my garden.

You are imagining it.
There is no source of energy to provide that amplification. There must be attenuation in the path of vibration from the many sources to your ear. The many vibrations will not all line up randomly in phase, to reinforce at your place.

If you hear a hum, it will have a particular frequency, not a band of
80 to 92 Hz.

 

[russ_watters]

Hi , thanks for reply. The two noise specialists used FFT spectrum analyzer and found perfect frequency match of that in my home to the data server hub, which supplies the town with the internet. Low frequency is according to BS4142 is under 200hz.

You're welcome, but you didn't answer most of my questions and the answer you provided is vague and appears to contradict your prior post. This limits the help I can provide.

 

[davenn]

placing ear to wall a very low hum, no noise.

That is a contradiction

 

[WWGD]

That is a contradiction

Maybe they assume a threshold decibelwise to consider it noise?

 

[Housey210]

Your use of the technical language requires some explanation. How can a hum not be a noise? What do you mean by a hum? What do you mean by a noise?


You are imagining it.
There is no source of energy to provide that amplification. There must be attenuation in the path of vibration from the many sources to your ear. The many vibrations will not all line up randomly in phase, to reinforce at your place.

If you hear a hum, it will have a particular frequency, not a band of
80 to 92 Hz.

You're welcome, but you didn't answer most of my questions and the answer you provided is vague and appears to contradict your prior post. This limits the help I can provide.

You're welcome, but you didn't answer most of my questions and the answer you provided is vague and appears to contradict your prior post. This limits the help I can provide.

Hi, it is pointless me using an app i do not understand. With my local authority saying they could not hear anything, and no evidence from their third octave test, they blamed my hearing. Establishing the maker of their testing equipment I contacted them. That manufacturer stated low frequency noise is hard to locate unless one has an idea of the source. I did, the internet hub just 70 mtrs away. In addition the manufacturer stated the preferd measuiring is FFT and not third octave which UK councils use due to cost of software licence. Armed with that info I sent the council's report to an accredited noise consultant, low frequency was present with two bands exceeding that as stated in NANR45. NANR45 quoted to be used for lfn in the BS4142 standard the UK councils use, BS4142 aslo states this BS NOT to be used for lfn. The council also failed to conduct a test at hub just 15 mins in my home at 4pm, the worst effected time. I was no forced to engage the professional services of an accredited noise consultant. Establishing a tonal element in my home we walked around the area. The only matching freqency, the west elevation of the hub. ( Put to the operator they confirmed that spot is where the rectifier is located, converter of 415 volts AC down to 24 v dc.) However the consultant said it was not air bourne, he could not hear anything in my home nor hub. Engaging a second consultant ground sensors where installed in my home and syncronised data logger in garden to rear of the hub. Again a perfect match, given a range of 80-92 hz. This consultant could hear the humming in my home, so too a councillor and local magistrate. The consultant requested the council instal digital loggers in that hub and home, they refused. The operator of the hub is a multimillion pound global internet supplier. The hub is built over a drain, there is also a drain to the side, both are 9 inch dia. A camera down the drain last week and a 6 inch branch has been found entering my garden, which is dead as i have new drain out to front. That dead leg goes to the back wall of the house and how far way is my next task but at a guess I woild say about 2-3 mtr away. What I am hearing in my home is a 24 hr constant home which goes so loud the windows rattle. It can also be felt underfoot. Sound, measureable by a sound meter, noise- subjective as we all hear differently. Of The drain the hub is built over that leg is dead, the drain to the side is free flowing and as it goes up through vent pipes, open. However there is branch at one end. The leg at my home is closed. I am saying vibrations from the servers, the driving force, are travelling through concrete slab into drain pipe and along its length. The dead leg drain in my rear garden is at 90 degrees to the main run and thats where i think the issue is. thanks for your time.

 

[Housey210]

Your use of the technical language requires some explanation. How can a hum not be a noise? What do you mean by a hum? What do you mean by a noise?


You are imagining it.
There is no source of energy to provide that amplification. There must be attenuation in the path of vibration from the many sources to your ear. The many vibrations will not all line up randomly in phase, to reinforce at your place.

If you hear a hum, it will have a particular frequency, not a band of
80 to 92 Hz.

hi, thanks for input. No imagination, heard by all in family, two neighbours, local councillor and magistrate, accredited noise consultant. 15 min test by council not meaningful, 4 days data logging with ground sensors is. the 80 to 92 hz is the data quoted in their report, as too not air but ground bourne. I'm a joiner, not scientist, so lingo may be odds to what is the norm. Sound, measureable with sound meter, noise, subjective as we all hear differently. What I hear in the home can not be heard outside. Very low hum can be heard at hub. This can only be vibrations from a driving force. thanks your time

 

[Baluncore]

No imagination, heard by all in family, two neighbours, local councillor and magistrate, accredited noise consultant.

The imagination I refer to is your connection between the data hub, the clay pipe, and your home.
The credibility of the witnesses / observers is irrelevant, they observe, but have no geotechnical skills to make the hypothetical underground connection, that you have now become fascinated by.

Pull the main switch or breaker on your house at night.
Does the annoyance go quiet? If so, look for an air circulation fan.
If not, get a noise generator to raise the noise floor in the house, or move your bed in the room.

 

[Housey210]

Your use of the technical language requires some explanation. How can a hum not be a noise? What do you mean by a hum? What do you mean by a noise?


You are imagining it.
There is no source of energy to provide that amplification. There must be attenuation in the path of vibration from the many sources to your ear. The many vibrations will not all line up randomly in phase, to reinforce at your place.

If you hear a hum, it will have a particular frequency, not a band of
80 to 92 Hz.

The imagination I refer to is your connection between the data hub, the clay pipe, and your home.
The credibility of the witnesses / observers is irrelevant, they observe, but have no geotechnical skills to make the hypothetical underground connection, that you have now become fascinated by.

Pull the main switch or breaker on your house at night.
Does the annoyance go quiet? If so, look for an air circulation fan.
If not, get a noise generator to raise the noise floor in the house, or move your bed in the room.

Would you spend £3000 having first not switched off mains incoming lecky? the scientific data logging over 4 days can not lie, the source is ground bourne, the call from the expert witness is for the transfer path to be investigated. Odd that having put a leaflet around town telling the story to good folk, and the £200k remunerations of the councillors, 5 vans pulled up at the hub and over the weeks ripped out old servers! One hell of a coincedence the humming lessened.

360amp rating plate on one piece of equipment i noted. Air con units / refrigeration cut in and out, the humming is a continious tonal element. It is every room of house. In addition some in the house at rear and one down road can hear humming in their property, they too connected that sewer the only difference their drains still live with vent pipe, my old drain is a closed pipe.

 

[Baluncore]

I don't think you want to resolve this. You want to maximise the attention and confusion, by trickling in as much irrelevant information as possible.

It is every room of house. In addition some in the house at rear and one down road can hear humming in their property, they too connected that sewer the only difference their drains still live with vent pipe, my old drain is a closed pipe.

That might suggest that the sewer/organ pipe network is resonant. It would be due to the low-speed air column within the pipe, not the clay nor the pipe. Have you opened and vented your sewer pipe? Did that change the sound? What if you close the sewer pipe at an inspection port, then half fill the pipe with water?

It may be more relevant if your houses are built on a flat geological slab, such as a drained swamp, over a more solid geological base.

Isolation mountings under equipment in the data-hub should prevent radiation of ground noise, but there is no certainty that is where the noise originates from. There are many alternatives. Your distance from the coastline, railways, highways, mines, or industry also come into the equation. Where is sewage processed? How is water distributed in your area, are there any pump stations nearby?