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Alex

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Hello, I noticed standards for building vibration use peak particle values (PP displacement, PP velocity or PP acceleration). I have made some search but didn't manage to find any good explanation what are the peak particle values. Well there is some theory everywhere that you have to measure particles (molecules) movement...

I wonder what does it mean in practice. What does the measurement equipment look like. Is it possible to measure it with classic piezo accelerometers and analyzers like CSI 2140 or do you need some special equipment. 

Do you guys have any experience with these type of measurements?
OLi

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It may come from blasting? I don't recognize that. Here we use accels nowadays and some magic numbers in velocity mm/s and amplitude microns but I don't remember if it is a local building code or ISO standard. We used to make blast monitors and then it was just a vibrometer recording the max value during a blast sequence when building but now they are more fancy with FFT and stuff.
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Robert U

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Here is a glossary that has definitions  Updated link

http://www.acoustic-glossary.co.uk
MarkL

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Quote:
Originally Posted by Robert U
Here is a glossary that has definitions

http://www.acoustic-glossary.co.uk/definitions-p.htm 


Link is not working
seanddd

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This is what I found doing a Google search (same as the link above). 

VIBRATION (PPV) – ALL THE ANSWERS!

What is vibration and where does it come from?

Ground vibrations are associated with different types of elastic waves propagating through the ground. These are surface waves, and bulk longitudinal waves and transverse waves (or shear waves) propagating into the ground depth. Typical frequency range for environmental ground vibrations is 1 – 200 Hz. Waves of lower frequencies (below 1 Hz) are usually called microseisms, and they are normally associated with natural phenomenae, e.g. water waves in the oceans.

Ground vibration is measured in terms of Peak Particle Velocity (PPV) with units in mm/s or mm/s-1. It should be noted that the PPV refers to the movement within the ground of molecular particles and not surface movement. The displacement value in mm refers to the movement of particles at the surface (surface movement).

Environmental ground vibrations generated by rail and road traffic may cause annoyance to residents of nearby buildings both directly and via generated structure-borne interior noise. Very strong ground vibrations, e.g. generated by heavy lorries on bumped roads, may even cause structural damage to very close buildings. Typical values of ground vibration particle velocity associated with vehicles passing over traffic calming road humps are in the range of 0.1 – 2 mm/s.

The main sources of ground vibrations at construction are pile driving, dynamic compaction, blasting, and operation of heavy construction equipment. These vibrations may harmfully affect surrounding buildings, and their effect ranges from disturbance of residents to visible structural damage.

Alex

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OK, but how to measure it? Are our classic FFT machinery analyzers and software suitable?   
OLi

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In Sweden the limit for acceptance is 0.4mm/s and transients at 1mm/s and damage limit 4mm/s.
"Weighted RMS" this is the government railroad dept. web page statement. 
We used MCV transducers at the time and they could likely go down to 1-2Hz but I don't remember the exact range and accels could do the same now.
So depending on application, you need to monitor during the event, blasting, train passing and log so you collect the highest number or long duration
for extended work like sheet piling or general piling log the highest number each day with time stamp. These day data from dedicated systems are in 3-axis
simultaneously collected. About what a quick search found and what I remember. Different countries may have different numbers so your mileage may vary.

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