Passive Earthquake Proofing w/ Dry Stone
in [Basics]
|
From: Bret Cahill on 9 May 2010 22:54 http://en.wikipedia.org/wiki/Earthquake_engineering#Friction_pendulum_bearing "People of Inca civilization were masters of the polished dry-stone walls, called ashlar, where blocks of stone were cut to fit together tightly without any mortar. .. . . "Peru is a highly seismic land, and for centuries the mortar-free construction proved to be apparently more earthquake-resistant than using mortar. The stones of the dry-stone walls built by the Incas could move slightly and resettle without the walls collapsing which should be recognized as an ingenious passive structural control technique "
From: john on 10 May 2010 10:27 On May 9, 8:54 pm, Bret Cahill <BretCah...(a)peoplepc.com> wrote: > http://en.wikipedia.org/wiki/Earthquake_engineering#Friction_pendulum... > > "People of Inca civilization were masters of the polished dry-stone > walls, called ashlar, where blocks of stone were cut to fit together > tightly without any mortar. > > . . . > > "Peru is a highly seismic land, and for centuries the mortar-free > construction proved to be apparently more earthquake-resistant than > using mortar. The stones of the dry-stone walls built by the Incas > could move slightly and resettle without the walls collapsing which > should be recognized as an ingenious passive structural control > technique " But were they cut? I've heard that story before. It's hard enough to get a simple floor edging cut once to fit together around a corner- if the floor is tilted any way at all wrt the wall, you add in that 3rd dimension and things get *much* harder. I liked the trapped miner's story about the blocks being poured in place. Some kind of nano-concrete that sets up like stone. I also had a dream about large buildings-20-30 floors- whose entire sides were murals of various kinds. And the pixels making up the picture were cut stone blocks of different colors. But these blocks were highly regular, like cut by laser or something (magnetically separated?) john john
From: Bret Cahill on 10 May 2010 10:52 > >http://en.wikipedia.org/wiki/Earthquake_engineering#Friction_pendulum... > > > "People of Inca civilization were masters of the polished dry-stone > > walls, called ashlar, where blocks of stone were cut to fit together > > tightly without any mortar. > > > . . . > > > "Peru is a highly seismic land, and for centuries the mortar-free > > construction proved to be apparently more earthquake-resistant than > > using mortar. The stones of the dry-stone walls built by the Incas > > could move slightly and resettle without the walls collapsing which > > should be recognized as an ingenious passive structural control > > technique " > > But were they cut? They had to do _some_ chipping or they would spend all day looking for the right shape. > I've heard that story before. > It's hard enough to get a simple floor edging > cut once to fit together around a corner- > if the floor is tilted any way at all wrt the wall, > you add in that 3rd dimension and things get > *much* harder. Maybe you need to chew on leaves to get everything to fit. > I liked the trapped miner's story about > the blocks being poured in place. Some > kind of nano-concrete that sets up like stone. The plaster fell off after the last quake exposing these great cracks in the 18" - 2' thick concrete wall structure supposedly from an earlier quake decades ago. Several tenents vacated within days. The walls were still plumb / flat / straight and the concrete pieces still fit together so nicely I wondered if the extra flex from the cracks might actually be an advantage. Then I read the Inca article and was reassured even more. I suggested that the landlord shouldn't replaster. Kind of like post modern architecture, there's beauty in honesty as well as functional cracks. Damping must be pretty effective. Look at how many resistors they use in electronics . . . > I also had a dream about large buildings-20-30 floors- > whose entire sides were murals of various kinds. > And the pixels making up the picture were cut > stone blocks of different colors. But these > blocks were highly regular, like cut by laser or something > (magnetically separated?) A 4.5 + will often get incorporated into my dreams except I'm in a 9 story building made of sandstone . . . Bret Cahill
From: John Larkin on 10 May 2010 11:35 On Mon, 10 May 2010 07:52:45 -0700 (PDT), Bret Cahill <BretCahill(a)peoplepc.com> wrote: >Damping must be pretty effective. Look at how many resistors they use >in electronics . . . > Only a small minority of resistors are used for damping. In most products, none are. John
From: Bret Cahill on 11 May 2010 00:04
> >Damping must be pretty effective. Look at how many resistors they use > >in electronics . . . > > Only a small minority of resistors are used for damping. In most > products, none are. No wonder so many laptops break after you hurl them across the room! Bret Cahill |