Evening star., 1915-01-02
APPEARANCE A FACTOR
IN FUTURE OF CONCRETE
Limitation as to Color and Tone
Subject of Criti-
cism.

Tho future Of concrete in architecture
depends very properly upon appear
ances. The material has established
itself unassailably for its structural
value. Yet the delight of the public
in beauties of color. tone and texture
is deeply cherished, and while plain
concrete. without particular attention
to surface treatment, Is admirably
adapted for massive effects and while
it supplies a pleasing background for
the vines and shrubbery and flower
boxes OF the home. concrete must not
suffer the Limitation which this alone
imposes, says a writer in the Detroit
Tribune.
for its lack of variety, is not the con-
crete much more of which will be seen
in the near future, and enough OF
which already has been seen to make
1t certain that the possibilities OF the
material are not purely theoretical.
The Limitation Of concrete as to tone
and color which has been criticised
has not been, rightly speaking. iimi-
tation of concrete at all 1t Is the iiIhi-
tation merely of the material which is
used to bind together certain aggre-
gates which make concrete. The cabl-
net maker, with his pot of glue. does
not bedaub his whole work with the
material which is intended solely to
hOld tOSeIner certain plcCeS.
Why, then, if effects of color and
tone are desired. should the concrete
worker expose the binding material to
the effacement of those aggregates
which are in themselves beautiful?
Followed Least Resistance.
Concrete work. like other things,
has followed the line of least resist
ance, but education in the way OF max
ing the most of materials which may
properly be used in concrete is becom-
| ing more widespread. When more and
more Of the artisans discover the pos
sibilities for beauty which belong to
concrete construction, the lovers of the
beautiful in buildings will take even
more kindly to the material. They
must be shown. They have seen sc
much Of one-tone concrete that theil
| Imagination fails them in conceivins
ANYTHING more lively in this material.
portion of the aggregates, surface mn
ishes of practically any desired color
| and texture are obtained, the possi-
bilities being limited only by the mum
ber of different aggregates available
land their possible combinations. The
color is obtained from the exposed ag-
gregate, not merely by adding color.
Ing matter to the mixture. A grea,
u
the use Of the common aggregates tc
be found or easily obtained In nearly
all localities such as limestone, granite
or other stone screenings, marble chips
land different colored gravels and sands
| To expose the aggregate the film OF
mortar that fushes the surface neX'
the forms must be removed. This is
accomplished In several ways.
How Film Is Removed.
1t is done by sand blasting, by using
an acid wash quickly removed by
water, by means of compressed all
tools-picks and brush hammers-o1
by means of abrasive materials with
which the concrete surfaces are rubbed
Reinforced concrete combines the
tensile strength of steel with the grea,
compressive strength of concrete. THE
invention of reinforced concrete is
usually credited to Joseph Monier, but
his first constructions are antedated
by those of Lambor. who constructed
a small boat Of reinforced concrete and
exhibited it at the Paris exposition
says Turneaure and Maurer in theiI
principles of Reinforced Concrete Con-
! struction."
| Good cement. good clean stone and
| clean, we'll graded sand, properly pro-
portioned and adequately mixed, placed
and cured-these make good concrete
Concrete will be the poor mans ma
terial as we'll as the rich mans ma
terial and the average mans material
Those who provide homes for the poor
er classes in cities frequently are not
far-sighted enough to see an advan-
tage in material which means a
lower ultimate cost.