Most lime mortars cure well wet or dry, but tend to effloresce if kept wet
after curing, about like plasters do, but not nearly so badly. Do as
block/brick/stone masons do. Put it on as wet as will sustain the load of
the stone/brick/block, and just let it cure until cheezy enough to strike
the joints -- then leave it be.
Well ... I'm bedding the floor stones <graded 2"-2 1/2" thick> in a mix
of 5 parts masonry mix , 1 portland , 3 sand , and 1thinset mortar . This
gives a mortar that's really sticky when mixed on the dry side and stays
very plastic as it sets . Makes it possible to adjust a rock that's been set
for a few minutes without breaking the bond . I'm also laying on top of a
layer of tarpaper so differential expansion <wood sub , 3/4" Advantech with
1/2" OSB screwed and glued> doesn't tear things up . I'll be covering it
with plastic when I finish filling the joints . Then , it'll be the wall ...
which is a totally different technique . It'll also be covered with a vapor
barrier for a couple of weeks minimum .
Actually , I was being sarcastic when I asked that question ... I still
remember when my Grandpa poured the floor for his garage , several hours
after they finished troweling it he scattered some straw over it and covered
it with tarps to control evaporation . I had to be like 10 or 11 , which
would put it around 1962 or 63 ...
That's sure nice. I had a fun time with mortar when I did my first
cobblestone walkway set in mortar, but it has stood the test of time
(7 years) so far. It's harder to get a single stone's surrounding
mortar to reliquify for resetting, but it's doable. I used a thick
piece of wire made into an L-shaped hook to lift the low stones to
level, bouncing them up-and-down to get the mortar back under them.
How do you like the Advantech over regular ply?
Wow, they had concrete way back then? ;)
I set (actually, reset) my first fake stones yesterday. Four pieces
of stone veneer (limestone-like hypertufa) onto the outside of a
garage wall. Researching adhesives for it, I could either buy a $45
bag (50#) of thinset or use LiquidNails. I chose a tube of LN for
$2.39. It didn't even pretend to hold the stone up to the mortar, so
I looked around and asked the lady for a large plastic bag and some
old rags or something. She had 4 boxes of winter clothes in the
garage so I used some of those. I filled the bag with clothes, tossed
loosely into the bag, then squished it up against the stone, using the
other boxes of clothing to press against the bag. Worked just great!
Steady firm pressure all over the face of the stones, holding them to
the wall for the hours until the LN set up. I was applauded for my
ingenuity, which is always nice.
The unexamined life is not worth living.
It's great . Very stable , more rigid than plywood , and it doesn't swell
up and start shedding if it gets wet . This floor got rained on twice before
I got the roof on , no damage at all . Don't even think you can hand-nail it
though ... I used my framing nailer .
And even before , if you believe history !
Ingenuity indeed ! I'll have to remember that trick , bet it'd work on
reattaching almost any veneer product .
On Saturday, August 23, 2014 12:26:38 PM UTC-4, Jim Wilkins wrote:
"Ready mixed concrete was first used in Germany in 1903"
I assume that's the type this thread has been referring to. But even the Sumerians described concrete. The Sumerian timeline dates from 3000 BC.
On Sat, 23 Aug 2014 09:53:11 -0700 (PDT), walter email@example.com
Portland cement is "regular cement" in the US. In Western Europe, they
often mix in a large percentage of Pozzolan. Their strengths are
similar but Portland cement cures faster.
At least by 1000 BC, the ancients were making Pozzolan cement in much
the same way a lot of it is made today: fine-ground, reactive types of
volcanic ash, mixed with slaked lime.
Pozzolan has been used for thousands of years, while Portland cement
has been around for about 150 years.
On Saturday, August 23, 2014 10:36:26 PM UTC-4, Martin Eastburn wrote:
> Pozzolan, being made with volcanic ash, has the unique ability to cure
>in salt water. Piers and mooring points were done by the Romans and the
> Japanese before and during WWII.
Here: someone said in a: "textbook that saltwater will work, but the total compressive strength will be 10%-15% lower"
Plenty of rainwater in the south Pacific but making piers running out
into the lagoon requires large dams and pumps .. what a job. Or use
ash and the chemical reaction is different from Portland. If the cement
were 25% less one would just build better strength versions or just put
up with some wear. Once you have an out-of-water pier, a hard top
could be added - with or without rails for cargo movement.
Some under water projects for a sub refueling design showed the real
Martin who lived in the south pacific for some time.
You seem to be a history buff on concrete...
How is it that Henry Flagler could build concrete piers in the ocean
100 years ago in the FL Keys and have the concrete still be in great
shape. Meanwhile everything built more than 20 years ago is falling
apart in the Keys.
concrete is mostly about two things: post-tensioned structures and
ferrocement. I've just picked up a few historical tidbits along the
way. I have a really great book on ferrorcement (among several
others) that took me most of a year of spare time to read.
Back in Flagler's day, we overbuilt all kinds of sructures, because we
didn't have the engineering to build them closer to the limits. I'm
just guessing, but it could be something like that.
He might have researched the subject before he just made concrete.
My furnace isn't Portland - no water is stored. It is a different
process and is a chemical reaction that makes the bonds. You cook the
water out of it in a long slow ramp up. Water inside of cement can
Simply drop some molten metal on a concrete floor and you might have a
hole dished out. Blow cement at you.
His piers might have been high temp cement being very dense as well.
One never knows without a core and some tests :-)
He said "Georgia". He didn't mean the Soviet state of Georgia.
There's really not much in the way of pyrolytic or volcanic stone in
He went to Georgia because except for a little limestone, Florida's only
mineral commodity is (well, was) phosphates. Our sand is too fine for
He actually went all over the world to get the materials for the
bridges. The below water cement came from Germany, the trap rock came
from NY state.
I was wrong about Georgia. it must have been Germany I was thinking of.
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