The Monitor. [volume] (Woodstown, N.J.) 1884-1892, 1884-02-22
DIFFICULTIES OF BUILDING IN
WINTER.


hardened, the line of demarkation between
setting and hardening being by no means
clear, although said to be determined by the
loss of placticity. When this is quite lost,
however capitalization has ensued, and con-
seouently hardening, though not to its full
extent. Besides, what becomes of the phrase
g setting hard" if mortar does not harden
until after it sets? Evidently another term
is required to denote ultimate induration as
opposed to the hardening acquired by crystal
lizing. Lime mortar has been known to set
SO extremely hard that it has defed all fair
means to injure it when only two days Old.
Frost does not usually penetrate into mortar
Joints to greater depth than half an inch,
or thereabout, and common pointing that will
never indurate (however picturesque 1t may
be made to look with lampblack or other
wise) is chiefly affected by it. This sort
often stands when frozen, but peels or scales
off when thaw sets in. Perhaps few incidents
have caused more chickering's between build
ers and their supervisors than the failure OF
pointing from frost, and this because the con-
tract has not enjoined that the work was to
be delivered up complete and sound with all
damage or imperfections that may have arisen
during its progress repaired, rectifed, and
made good. Pointing executed with strong
lime and little sand we'll troweled and con-
solidated by pressure into the raked out,
cleaned, brushed, and wetted edges OF the
bricks is, like good struck and cut joint,
more adapted to remain unimpaired during a
severe winter than tuck pointed joint, how
ever accurately trimmed. When not brought
to smooth, impervious face, joints remain
porous, and are in danger of disagreement
from frost. A like disaster may happen when
they are not weathered to throw off water, or
through an oxidation of the water of crystal
lization occurring during freezing tempera-
ture. The porosity of Portland cement in
duces stucco made Herewith to fake and peel
off in frosty weather if cracked or laminated
through careless admixture or rendering.
This cement retains in setting considerable
portion of the water used in bringing it to
paste, and Notwithstanding that it sets quick
ly and parts with all superhuous water it
takes months to indurate and dry.
Frost is doubtlessly particularly detrimen-
tai to all green work, which requires there
fore, efficient protection in the shape of
boards, straw, and such like coverings. Ex-
ternal work must not be proceeded with dur
ing frost, nor while frost is in the materials.
In the one case there will be upheaval followed
by collapse, and in the other destructive set
Element Buildings, however, already rooted
in can be advanced during frost by stopping
doors and windows with screens and lighting
fires Concrete, which plays SO important
part in the stability of structures, should
never be made in frosty weather. In spite of
this fundamental precept some imagine that
it can be done with impunity, because hot
lime will take the frost out of the ballast,
without rejecting as to the effect on the
ultimate hardening its rapid rate of cooling
may exercise. Concrete made in temperate
weather, and exposed to frost, sometimes
shows minute cracks on its surface that are
the result of contraction; but these are too
to interfere with the permanent
expansion of concrete properly prepared with
hot lime or cement, and which, by its great
lifting power, affords so splendid means of
underpinning Portland cement concrete
compounded in frosty weather suffers re-
tardaton in setting, and consequently, its
perfect cohesion may be fairly suspected
when it eventually consolidates.
1t would thus appear that in addition to its
powers of weakening, disrupting, and gnaw-
ing, frost furthermore affects building ma
terials by squeezing them as far as its severity
will permit 1t is also evident that the diver
gence in their relative loss of bulk, through
contraction, is too Misunderstanding in the
case of continuous girders, etc., unprovided
with expansion arrangements-to produce
anything like dislocation when mixed up in
building, and attaining, or not, an approx
mately equal temperature. The sensation of
cold which is misleading, would give the
idea that such an attainment is impossible,
since stones and metal feel so much cooler
than timber. All inert bodies, however,
exposed to the same temperature, acquire it
within a reasonable time. There are of
course, instances when an even temperature
is never reached, as in the case of chimneys
ETC., presently noticed. AS to the motion
superinduced by contraction and expansion,