Historical Building Vibe Tolerance Limits 1

[271828]

I have been tasked with measuring elevated floor and wall vibrations in a historical building with delicate plaster, artwork, and artifacts. The excitation will be short samples of jackhammering and sawcutting on a floor below. The report will be used to inform the demolition contractor on which methods should be avoided.

I'm seeing PPV limits of around 13 mm/s and 0.5 in./s quite a bit in the literature.

I'm pretty sure these are ground motion limits. I haven't yet found limits on the PPV of the floor or walls. If anybody has a reference for this, I would appreciate sharing.

My thought is that 0.5 in./s at the ground would typically correspond to lower PPVs of the elevated floors and walls. Thus, the limit on the floor or wall might be 0.25 in./s or similar. Any thoughts on this?

If anybody knows of any gotchas or other pitfalls, I would appreciate sharing those also.

Thanks in advance.

 

[Strong]

https://files.ceqanet.opr.ca.gov/25...9JzxX2UDjczGnvesp8rG8-mgAOmzdbztbHl_GOkzz5zn0

Look at Class III or IV in Table 3

Other information on this search:

https://www.bing.com/search?q=build...e..69i57.9509j0j1&pglt=43&FORM=ANNTA1&PC=U531

https://www.osmre.gov/resources/blasting/docs/OtherReports/Historicalbldglimits1983.pdf

Walt

 

[271828]

Thanks Walt.

In the first doc, are those limits on ground motion or floor motion? If ground motion, any idea how to adjust them to get limits on floor or wall motion?

 

[Strong]

I believe the reference is for ground vibrations. Here is a search on that web site with many references:

https://ceqanet.opr.ca.gov/Search/serp?q=ground+vibrations

Typically it is difficult to get floor and wall motion from ground motion, since soil, foundation, and structural design could be significant factors (amplification and attenuation). You may find general criteria to correlate measurements with possible failure issues, like crackes in walls, etc.. I only worked on a few small projects of this type, and materials are not handy.

Walt

 

[271828]

Thanks again Walt.