The Detroit times., 1911-02-23
IL
sooD2

P=safe load in pounds per square
inches.
l=length OF column In inches.
d=outside diameter OF column In
inches
Ultimate compressive strength
Factor OF safety=S.
Wrought iron columns must have
SUFFICIENT sectional area so that the
stress In pounds per square inch
under maximum loading shall NOT
exceed seventy-five 75) per cent
OF that allowed for medium steel.
Soft steel stresses shall not ex-
coed eighty-five $3.50 per cent OF
those allowed for medium steel.
Columns In which the load II
transferred from one section to an
other by metal end bearings shall
be machined so as to give a true
Sec .. TENSION MEMBEI,s.
Tension members OF all kinds shall
have sufficient cross sectional area
at all points to support the maxi
mum load coming upon them with
stress that shall not exceed one
quarter (k) Of the breaking stress
ton varies owing to the cutting
of threads, boring or punching OF
holes or other causes, only the net
section shall be considered.
Sec. 10. TRUSSES. Trusses are
TO be considered as combinations
OF compression and tension mem
bers. and shall be designed accord
ing to foregoing regulations for
such members, and In accordance
with the rules OF practice recon-
mended In September. 1910, by tho
American Bridge Builders Asso-
citation. They shall be riveted or
pinned structures, as determined
by the conditions.
Sec, IL. PURLINs. Purlins may
be rolled or built-up sections or
trSssed angles; .p,no .rrs
plates must be provided under the
wall ends OF all beams. girders.
trusses and columns. OF such d.
mension to properly distribute the
maximum load upon the masonry.
according to the carrying capacity.
Of such masonry, as set forth In
Sec. 10. LINTELs. Linteis In
masonry walls shall be OF rolled
shapes or rolled shapes and plates.
Sec. II. R1vETS. In all riveted
work the holes shall be made one
diameter sisnsn q the then r, ,saser than the
Holes must be accurately placed
opposite each other and no drift
ing to distort the metal will be
permitted. IL the hole requires 10
be enlarged to admit the rivet IL
must be reamed and larger rivets
used.
Holes In steel three-quarter (k)
inch thick or less may be punched
to full diameter required, but for
steel OF greater thickness the
holes must be sub-punched and
reamed or must be drilled from the
solid.
Rlvets where driven, must COM
pleteiy I'LL the holes and have the
heads in full contact with the sur
face.
At all bearings. upon or under
the plates, etc.. the rivets must be
counter-sunk.
Where possible the rivets must
be machine driven.
Rivet heads shall be OF true
hemispherical shape and concern
trio with the axis OF the rivet.
Sec. 10. EYE BARS AND UPSET
E1p s EM Ss heads Of s penf bars s'r and
rod ends shall have upset ends
no weld will be allowed In the
body OF the bar. Steel eyes shall
be annealed and holes shall be
drilled. -
mineral paint before being put into
Milled surfaces shall not be
Sec. IL. ERECTION OF STEEL
FRAME. In the erection OF steel
frame the various members shall
be kept plumb and true by sum
cient temporary bracing In each
story while the riveting and en-
CLOSING masonry In being done.
Sec. is. STEEL CUT BY OTHER
CONTRACTORS. The working
section OF beams, girders. columns
or other Important members shall
not be cut or punched by other
contractors without the approval
of the DsgartmTsNnss p q sqi,Sinss AND
TESTS. The Department OF Build
ings may require at any time. Ger.
tined comics Of mill, shop or field
inspectIon from recognized experts.
OF ali steel and iron work to be
used in any building.
Tests of iron and steel shall be
made at the place OF manufacture.
from tests pieces cut from the nm
ished material, and all such tests
where possible shall be made dur
ing the rolling or casting OF the
material, due notice being given
the Department OF Buildings OF
such rolling or casting and the
not TO delay such rolling or cast
when the Department OF Build
fngs desires TO make shop or field
inspection OF finished work or ma
terial. due notice shall be given TO
the Department and said Depart
ed and certified II possible on the
same day. otherwise on the next
ARTICLE XIII.