How post on stone traditional construction holds up in earthquakes?

[Latimerias]

Hello,
When looking at post on stone connections where there is no fastener connecting the two, just gravity, I struggle to see how these structures would not slide off the stones in an earthquake. In one of the photos they place a more rot resistant wood in between stone and post, and in the other the post is directly on stone, and it mentions using crushed lime to test the adhesion between post and stone. How are these connections withstanding time? Thank-you.

https://res.cloudinary.com/engineering-com/image/upload/v1716759762/tips/248367332_1250010908745695_7007566382941923380_n_afezuo.jpg[/img]com/image/upload/v1716759748/tips/DSCF6201-2_shpkjl.webp][URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1716759748/tips/DSCF6201-2_shpkjl.webp[/url]

 

[Greenalleycat]

Who the fuck is doing new construction like that?
I live in a high seismicity country and this would never fly in new construction
However, there are many equally terrible foundations that I've seen all round our city which have experienced large earthquakes and are still standing

I think the reality is you get a whole bunch of highly non quantifiable effects that normally make it "ok in practice" but you could never put a signature to
Basically your lateral resistance is the friction between the interface and, as long as you don't lose gravity support, you probably a) reduce seismic loads through slip b) dissipate energy through friction c) get some element of self-centring as the earthquake shakes around and stuff ends up roughly where it started d) earthquake duration and magnitude would be huge factors - larger earthquakes are far more likely to tilt these things off

 

[1503-44]

Who TF? Japan of course.

This search "Japan post on stone foundation" uncovers quite a few examples.

https://duckduckgo.com/?q=japan+post+on+stone+foundation&t=brave&ia=web

https://youtu.be/RsD_i6WVkL4

In fact, I found the same picture uploaded by the OP.

https://www.blackpine.co.nz/black-pine-resources/ishibatate-traditional-japanese-construction/

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Latimerias]

Yes! Primarily referring to Japan for their seismic activity. I had trouble finding resources for old buildings using this foundation method that would have already experienced a seismic event but i saw many pictures of temples with this system. I've also found these two articles which talk about the traditional techniques used in pagodas for dampening but it doesn't seem like having these central weights would be able to keep the exterior posts from sliding off of their small rock footings.

https://www.u-tokyo.ac.jp/en/about/publications/tansei/10/75-recovery-buildings.html

https://engines.egr.uh.edu/episode/1299

 

[1503-44]

I would think that ancient temples still standing would be proof of concept.
Low density wood and paper wall structures probably have weight x Friction factor >> mass x acceleration. The flexibility of wooden joints may also contribute to distribution of shear loads to all columns/supports before any one of them snaps. It might be worth trying to contact the authors.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Once20036]

I was always under the impression that this isn't a flat interface, but that there's a lot of three dimensionality in those joints. Like this:

In the case of the two dissimilar woods, there may be some joinery that isn't visible in the pic.

 

[1503-44]

Yes, I noticed that in some of the descriptions, which would tend to increase friction. But on the other hand, some installations looked like pretty flat rocks. Pine seems to be a favored material. Perhaps they use the resin to get some additional bonding too (?).

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."