Omaha daily bee., 1907-08-19
CONSTRUCTION is DEFECTIVE
Collapses of Concrete Buildings Due to
This Cause.
EXPERT GIVES HIS OPINION
Says More Disasters WIN Fellow
Unie"" Greater Precautions
Are Taken by
Builders.
QFrom a Stan Correspondent)

From a STAFF Correspondent)
WASHINGTON, Aug. 1s-(special.) THE
recent collapse of number of reinforced
concrete buildings with loss of life and OF
several hundred thousand dollars has
brought forcibly to the attention of struc-
tural material experts the need for an i'm
mediate revision of the building regulations
OF the great cities of the country 1t Is
declared that inattention TO this new ma
terial on the part of officials OF munich
palities and the hsphazard manner in which
| 1t is being handled by some contractors
| have led to a most serious problem and
! will result in more disasters unless there is
a remedy at once.
Richard L. Humphrey, expert in charge
of the United States Geological Survey 8
| Structural Material laboratories in st.
Louis, Mo-, and Norfolk, Va. declares that
the danger OF collapse Of concrete struc-
lures exists in nearly every important city
in the United States.
| Il have examined carefully nearly every
one of the buildings that have collapsed
within the last year" says Mr.. Humphrey,
| ''and in every instance the fall of the
structure has been due to carelessness Of
construction. From what have seen OF
other concrete buildings in process of con-
struction, 1 am satisfied that the same
errors are being repeated and that further
collapses will surely come unless the Of
hcials OF the cities take the question in
hand now. This danger of careless con-
struction confronts nearly every city or
the country and it is miracle to me
that more concrete buildings have not col
lapsed.
Building Laws Faulty.
Tn to ral
every city in the United States should re-
wise its building laws in such manner
that either the owner or the contractor
of concrete building shall be compelled
to employ competent inspector whose
duty it shall be to follow every detail Of
the construction from the beginning of the
/ foundations to the completion of the roof
| New York, st. Louis, Boston and Phila-
delphia have either prepared or are now
preparing regulations governing concrete
construction.
THE science Of concrete construction Is
not yet thoroughly settled and until it is,
the greatest care should be taken in the
use of the materials. Concrete, by reason
of it's superior qualities, especially its re-
sistance to fire and its cheapness, Is being
| used extensively in these days and will be
employed still more in the future. 1t is
comparatively new material and until its
properties are fully known and appreciated,
the greatest safeguards should be thrown
about 1t. There is o prevalent idea that II
can be used by unskilled laborers. That is
an error which has led to serious conse-
auences While It is true that unskilled
labor can be employed to large extent.
concrete construction requires the same
care and attention to details that is de-
manded by first class construction with
other materials
Concrete Not Properly Mixed.
Some Of the causes that have produced
failure are carelessness in proportloninS
and mixing the concrete; poor or unsuitable
sand, stone or gravel; poor joints In the
forms and insufficient and incorrectly placed
reinforcement and bad alignment Of the
work.
Each failure tends to discourage the
use of concrete. for the reason that 1t Is
almost universally attributed to the ma
terial rather than to the improper con-
ditions under which 1t was used. The fai-
ure of a reinforced concrete structure py
reason of improper design, poor materials
or bad workmanship is no more an argu-
ment against it's use than the collapse OF
a steel structure under similar conditions
Ia an argument against the use of struc-
tural steel in construction
'"rhe geological survey in connection
with its experiments mas made II a point
to investigate promptly the failure CT
concrete structures and the collapse or
these already examined has been due to
carelessness on the part of the CON
tractors or defective design or forms ana
not to the materials used.
"In the last ruined concrete building
I inspected found many evidences of
carelessness in construction. The FORMS
used were the bad features; the joints
were not tight the supports were light
and for the roof had to be spliced. The
alignment of the work was very bad;
the columns did not center over each
other and the lower sides of the beams
and girders were not only not level, but
had also sagged, indicating that the
forms we're not of suficient stiffness.
reinforcement Poorly Done.
"Further carelessness was shown In
placing the reinforcement; the rods were
too close in the girders and beams and
the splice of the sheets of expanded
metal in the floor slabs did not appear
to be SUFFICIENT. Little attention appears
to have been paid to the column connec-
tions While there were many points In
the construction which were not as they
should be and certainly not in accord
ance with good practice, none Of these
can be regarded as the cause of the fall
ure There were indications that the
building was being rushed to compile
tion, with little attention to vitality i'm
portant details. The evidence shows that
the contractor was using the lumber
forms In another building and was there
81, hafn ha
concrete had become sufficiently hardened
10 support itself. Again, the atmos-
pheric conditions at the time were not
conducive TO a rapid hardening of the
concrete. Despite all these defects in
construction, the collapse OF this build
ing was undoubtedly caused by the pre-
mature removal of the supports by an
ignorant workman.
'aThe geological survey through it's
technologic branch, is now conducting
valuable experiments at it's laboratories