Turner County herald. (Hurley, Dakota [S.D.]) 1883-19??, 1911-12-28
Concrete On The Farm
By Prof. Robertson Cock, Engineering De.
partment, State College.

The more progressive of our farmers
are today much interested in the use
of concrete to still further improve
their farms, and we'll they may be for
the use of concrete on the farm is just
as desirable and just as economical
as is its use in tae cities. 1t is used
in the cities because it is strong,
durable. and fireproof; economical to
use,and good to look at. These same
qualities are TO be sought for on the
farm
1t is not the purpose OF this article
to take up in detail the many uses to
which concrete may be put, butrather
to touch upon the selection of the ma
terials to be used with the cement
in its manufacture
Concrete is an artificial stone. When
we'll made it has all the good quail
ties Of stone and in addition, it has
the Very great advantage of being
made just whore it is wanted and in
exactly the shape required. The cost
is not great where a supply of good
sand and gravel is near at hand.
Importance OF Gravel.
AS concrete is made up in the pro.
portion Of one part of Portland Ce-
iEent to from to 8 parts of sand ard
gravel, tic Importance Of the sand md
gravel is much greater than is usually
supposed. Indeed the choosing Ct
these substances, calle,, the aggregate,
where suveri.i solr@.s of supply ere
available. is G. mcve Importance usu.
ely thaa the che ing G. II = Gem eat
iAsels. 10 larse af.i ,.e,! lnoNn re.
melt company won,d dare to allow
'ooI GelJ ent e Ny' sc-.i out uud "
their br.nd So ilat Purchasers are
fairly 81 se whom bl. log y,cM known
Er;.rGs # getting good oe lent We
do not ul-.riake to say, however. that
some LraIds Of ceiireLt are rot strong
er and MN net csrsy more sard than
others. THIS Cain oaly he told by ex-
act 'abcra tory tests, however.
Gravel ID be suitable Tor use in CON
cretc @erl. should re hard and cl aan
and Of all sizes, from the smallest u0
to the largest that can he easily used
in the work to be done, or mixed in
the mortar box or MIXER. Too much
grave OF oll sizes because suct a era
vel wil pack closer and leave less
voids O. cpcnir y beuween the stones.
and Hill, therefore, take less sand and
cemal, and viii give denser, strongr,
concr
Gave if 1t contains chunks of clay
or dirt or If the stones are covered
with coating of clay should be wash
ed before being used 1t Is important
that the cement and sand mortar come
IN direct contact with each stone and
lsyer OF clay in the stones prevents
this. Whore water is plenty washing
gravel is not at all difficult.
Choice Of Sand.
The choice of the sand is the most
important part of the preliminary
work. A coarse. clean, hard d-grained
sand is best The thing to be sought
for always in concrete work is density,
or compactness. The densest concrete
is the best concrete. The sand grains
which will make TIC densest concrete
is one which Will include all sized sand
grains with a large proportion of the
coarse ones. OF all the South Dakota
sands analyzcd and tested by the Ex-
pcrimental laboratory of the South Da-
kota State College. not one has been
found which was not improved and the
resulting concrete made stronger by
the screening out of some of the finer
particles. So we arc fairly safe in
, saying OF South Dakota sands that the
coarser the sand tho better, other
things being equal.
A very dirty sand, one containing
much clay or loan should be used with
great caution. if at ALL To determine
whether sand is dirty. take a quart