ground-borne vibration mitigation

huangyhg

ground-borne vibration mitigation
say you have a research facility with vibration-sensitive equipment, and it's immediately adjacent to a train track.  ground borne vibrations are induced on the structure.  it is being proposed to provide granular material ("riprap") under the spread footings to help mitigate vibrations.  does anyone have any experience with this?  or a possible reference?  in a recent post i know 271828 alluded to some uk references that i am in the process of tracking down and reviewing, but i thought i might solicit some input/advice about this idea.
many thanks.
a very cost effective method could be to use trenches around the perimeter of the building, the depth depending on the amount of mitigation needed. this trench could then be bridged. i have seen this done often in india where i come from. hth
years back when i was in school in brooklyn some of the students were doing sensitive tests and had to wait until early hours of the morning when traffic on the nearby subway was minimum. the pan-am building [ now met-life] over the grand central station has a layer of lead under the foundation to reduce vibration from the trains.the other approach if possible is to use vibration isolators on the instruments.
jk, the uk references won't be helpful for this.
i've read about trenching, but have no idea how well that will work.  i'm interested in this problem, but haven't worked on it enough to be helpful.
i've used vibration interception trenches successfully as a temporary measure when using dynamic compaction between the work site and adjacent structures and services.
vb