New-York tribune., 1908-04-20
TO WITHSTAND FIRE
The Federal Government Studying
Flame Resisting Materials.
From The Tribune Bureau

Washington,
sea. Mass, last Sunday which rendered ten thou
sand persons homeless and resulted in a property
loss OF several million dollars. following as it did
closely upon tho heels of the Boyertovu PENN
and ColnwoOd COhio) hoIocausts. with their ter
rible loss q life has added significance to the fire
tests Of building materials being conducted BY the
United States geological survey
The federal government owner OF buildings val
ued at more than $500 900. and spending s000ono
every year for new structures throughout the
try, conducted these test in order that its arCh
tects and engineers might have definite information
concerning the fire resisting qualities of the differ
ent materials Of construction to the end that the
governments buildings may be properly safe
guarded from fire within and without.
The government engineers have long cOntended
that with present methods Of construction con
faSraton resulting in the destruction of millions
OF dollars worth Of property and the sacrifice OF
human life is possible in every city of any size
in the country Their position has been proved in
tragic manner by the Baltimore fire. the'dre fol-
lowing the earthquake in San Francisco and that
in Chelsea
1t Is the belief of the engineers that these great
fires are unnecessary and can be prevented by the
! erection of proper freproof buildings The govern
ment does not insure it's buildings against loss by
hre but bends its energies toward making struct-
ures hreprocf small fraction of what would
be paid to insurance companies in premiums is be
ing spent in finding out the materials that are hest
adapted to resist fire.
The first OF series OF elaborate tests has inst
oeen completed by the structural materials lab
oratories OF the geological survey under the d.
tectlon or Richard L. Humphrey. engineer in
tharSe. The tests conducted al the fire nm
derwriters laboratories in Chicago and were made
possible by the cooperation Of tho National BOARD
OF Fire Underwriters the National Fire Protec
toh ASSOCIATION Thirty panels Of various build
! ing materials including concrete building blocks
common. hydraulic pressed and sand lime bric.
concrete of gravel. cinder limestone and granite
glazed building and partition Gotta tile; sand
stone, granite and marble building stone vrars
tested The materials were subjected to the direct
| application OF heat for two hours and were +bar
| Immediately drenched with water An s4,rt -,
Hldde 10 obtain maximum temperatura NJ IN
desreeS Fahrenheit within half an hour fter start
i"s tHe tests and TO maintain this Temperatures ~
half hours '''e succeeding
Inc building materials were placed in o ,t.1
panel which when arranged for the fire tot
lormed one side Of the furnace In the r,rs,a
gas names were forced by a blast II air ag,i~,t
one side of the panel. After two bo,,rs IN. -
was brought from the furnace and the -.
turned on from hose with A pressure ~ ts+-.
J pounds TO the square inch
me conditions under which these tests were r,,ta
80 unusually severe, and as none Of the ma
'erla's passed perfectly it proved =, good to.+ -
1oi"td'au'e purposes The temperatures ,,s4d
NouIu hardly he reached in an ordinar, Ara 49,,
| might be in Il conAagration
""I'e 'neSe tests are not conclusive being only
- 9'''N'Is oI general line Of Investigations 4"
Sdd director Smith of the Geological SUrrev ..,b
: bring out number OF Irnnortan+ fa,.. r.
panels probably withstood the tests better ,b,,
any other materials. There were two lots OF com,
49, 'NN teS'eu one was an unused recently
manufactured brick and the other a brick n -
Hdd oeen IN an engine foundation for soma ,,sar,
Inc IatteF seemed 10 withstand the test the hot
/ ter tHty per cent OF the new bricks varo .n,t.
"hlle o. 10 10 per cont OF the old bricks were nor
s ui'I''seu. Inc oflcks at the back of the panel
Were ehuFeiy unafected. The hydraulic pressed
orlcKs stood the test better than anv other ma
teral No damage was apparent u,ra,e,,.ar -.
lhe hrlng and before the water was annIied MI
a''Iough number Of the bricks cracked 70 per
cent oI 'hem we're found To be intact after the
quenchng Of the flames. There was snDarentIy,
little difference in the strength Of the brtcr,s bs
fore and after firing The natural buIding s,onaz
behaved the worst CT all the material tested Thu
almost complete destruction of these stones nre
oludes any comparison between them The sand
stone panel entirely collapsed after the test
was started"
The testing engineers reported that il was 4ir-
hcult to determine whether the concrete made
from limestone, granite, gravel or cnders sus-
tanned the least damage. The surfaces were all
/ rather badly pitted by the fire and washed swav
by the stream OF water. The test was unfair TO
ctnder concrete, the sample of cinder was moor
containing a large percentage of unburued coal
which iSnted and left the surface Of the concrete
much pIttcd The granite concrete probably be-
far into the concrete. probably not more than one
and Oue-half inches The evidence shows that
even at this depth the temperature was cornpara-
lively low. The rapid heating of the face Of the
concrete, while the back remained cool caused tb,,
concrete to crack vertically for some distance hack
from the face. The cracking of the concrete can
be avoided. it is believed. by using metal rein
forcemeut which would distribute the effect of
! the expansion. The tests also brought out most
' clearly the low rate which the heat ira els
through concrete. This is OF the desirs bic
qualities in materials intended for ireproodns
purposes
+ Linen tags which placed IN the hollow
concrete blocks when they moulded were
found To he undamaged after the ire test In
/ many instances the hollow blocks split alter being
subjected to the hre and test. 1t was no
ticeabIe that the richer the mortar used in these
blocks the less they affected by the test.
The mortar mixed with the greatest percentage OF
/ water gave the best results. The wetter richer
, mixtures in these tests stood out apparently un-
damaged in contrast with the damaged faces OF
? the eaner dryer blocks 1t Is apparent that one
OF the causes Of weakness in the hollow cement
building blocks is in the weakness OF the con-
crete due to too dry and thin mixture, which.
/ coupled with the thinness Of the webs the thin
pieces connecting the walls of the blocks TO give
strength provides insufficient. strength to resist
the rapid expansion of the face Of the blocks
: under test By making the webs thicker they can
| be made 10 stand the fire test satisfactorily.
FATHER" CHADWICK SERIOUSLY ILL.