[Strawbale] Rlimestone screenings

[Shody Ryon]

When I was in Puerto Rico, caliche was used some times
on dirt roads. So I googled it:
http://en.wikipedia.org/wiki/Caliche_%28Mineral%29

Caliche is a hardened deposit of calcium carbonate.

Building applications

Caliche is used in construction worldwide. The caliche
reserves in the Llano Estacado in Texas can be used in
the manufacture of Portland cement; the caliche meets
the chemical composition requirements and has been
used a principal raw material in Portland cement
production in at least one Texas plant. Where the
calcium carbonate content is over 80 %, caliche can
also be fired and used as a source of lime in areas,
which can then be used for soil stabilization.

When mixed with small amounts of either pozzolan or
Portland cement, caliche can also be used as a
building material that will exceed the building code
requirements for unfired masonry materials. For
example, caliche was used to build some of the Mayan
buildings in the Yucatán Peninsula in Mexico. A
dormitory in Ingram, Texas and a demonstration
building in Carrizo Springs, Texas for the United
States Department of Energy were also built using
caliche as part of studies by the Center for Maximum
Potential Building Systems.

In many areas, caliche is also used for road
construction, either as a surfacing material or, more
commonly, as a base material. It is one of the most
common road materials used in southern Africa. Caliche
is widely used as a base material because it continues
to accumulate and gain strength over time.

When we used it, it came as a wet sand that had some
gravel mixed in. It also had a semi cement texture to
it. when we placed it, over time it compacted. walking
on it or driving on it made it hard(er).

I was noticing that it has a high pH. I am concerned
that calcium carbonate, as well as concrete would,
over time, degrade 6 mil polyethylene construction
plastic sheeting. Is the plastic sheeting usually
embedded in sand?
When I poured concrete, we poured it onto the plastic.
When I removed concrete, the plastic always seemed
degraded to me, like it had been in the sun light.

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com