And what country can preserve its liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.
Not sure that's a good method. I seem to remember that stone can really resist compression, but shear force not so much. Ready to be corrected on this by an engineer.
These are paver stones though, meant to be in place with minimal stress and strain. The dutchmen are just to keep them from shifting, and I'm guessing they date to an era of horse and carriage traffic - not heavy vehicles. Beautiful work.
Anon, you are correct. You can even see that the leftmost tenon is cracked right across the joint between the two stones it connects. This works great in wood because it the strength modulus is very different as a function of grain direction. Rock has no grain (at least this kind...sedimentary can be stronger in the deposition plane). This repair method in rock would have worked better had they used cylindrical pins instead.
Reminds me of repairs to large wooden bowls which have cracked.
ReplyDeleteNot sure that's a good method. I seem to remember that stone can really resist compression, but shear force not so much. Ready to be corrected on this by an engineer.
ReplyDeleteThese are paver stones though, meant to be in place with minimal stress and strain. The dutchmen are just to keep them from shifting, and I'm guessing they date to an era of horse and carriage traffic - not heavy vehicles. Beautiful work.
DeleteAnon, you are correct. You can even see that the leftmost tenon is cracked right across the joint between the two stones it connects. This works great in wood because it the strength modulus is very different as a function of grain direction. Rock has no grain (at least this kind...sedimentary can be stronger in the deposition plane). This repair method in rock would have worked better had they used cylindrical pins instead.
ReplyDeleteOr a stone ball out of sight in the middle of the wall with a hemisphere in the top and bottom stones. I saw a dismantled wall with that once.
DeleteI'll bet whoever did this was paid by the hour.
ReplyDeleteUnlimited expendable labor force.
DeleteI think the Romans did a similar thing with poured lead. Earthquake resistant?
ReplyDeleteThose "dutchman" are much harder in stone than wood...might be not for repair but artistic flair.
ReplyDeletePaul, I had the same thought.
ReplyDeleteBoeing should take note.
ReplyDelete