The Detroit times., 1911-02-23
LIZ
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P-ssfe load in pounds per square
i-1length OF column in inches.
d=outside diameter OF column In
inches.
Ultimate compressive strength
10000 pounds per square inch.
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 fve (s5) per cent of
those allowed for medium steel.
Columns in which the load In
transferred from one section to an
other by metal end bearings shall
Sec. Q. TENSION MEMBERS.
Tension members or all kinds shall
have sufficient cross sectional area
at all points to support the maxi
mum load coming upon them with
stress tl,st. shall not eSceed one
quarter az yhof the breaking stress
OF the Material Where the Sec
ton varies owing to the cutting
OF threads. boring or punching or
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 he 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. II. PURLINS. Purlins may
be rolled or built-up sections or
trussed angles.
Sec. IL. BEARING PLATES
Standard steel or iron bearing
plates must be provided under the
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
this Ordinance.
Sec. ~. LINTELS. Lntels In
masonry walls shall be OF rolled
shapes or rolled shapes and plates.
Sec. ~ R1vETS. In all rivetsd
work the holes shall be made one
eighth (h) inch larger than the
diameter of the rivet.
Holes must be accurately placed
opposite each other and no drift
u a. = "
permitted. II the hole requires 20
be enlarged to admit the rivet IL
must he reamed and larger rivets
used.
Holes in steel three-quarter C%)
inch thick or less may be punched
10 full diameter required, but Tor
steel OF greater thickness the
holes must be sub-punched and
reamed or must be drilled from the
solid
Rivets where driven. must COM
pletely MI tho holes and have the
heads in fun contact with the sur
face.
the plates. etc, the rivets must be
countcr-sunk
where possible the rivets must
be machine driven.
RIvet heads shall be OF true
hemispherical shape and concen-
trio with the axis of the rivet.
Sec. IS; EYE BARS AND UPSET
tures the heads OF eye bars and
rod ends shalt have upset ends
no weld will be allowed In the
body of the bar. Steel eyes shall
be annealed and holes shall he
drilled
shall ha ns,n a. before being pUt into
HlueId' paiht
Milled surfaces shall not be
Sec. IL. ERECTION OF STEEL
FRAME. In the erection OF 2 steel
frame the various members snail
be kept plumb and true oy sum
Client temporary bracing In each
story while the riveting and en-
closing masonry IL being done.
sec. is. STEEL CUT BY OTHER
CONTR ACTORS. The working
section OF beams. girders. columns
or other important memoers shail
Contractors without the approval
az the Department. OF Buildings.
Soc, 10. INSPECTION AND
TESTS. The Department OF Build
ings may require at any time. Ger.
inspection from recognized experts.
Of all steel aud iron work TO be
used Ia any building.
Tests of iron and steel shall he
made at tie place OF manufacture
,ron tests pieces cut from the iin-
ished material. and all such tests
where possible shall be made dur
inc the rolling or casting OF tue
material. due notice being given
the Department or Buildings OF
such rolling or easd,ng anu tse
not 20 delay such rolling or cast
when the Department OF Build
ings desires 10 make shop or held
inspection Of FINISHED work or ma
tSriai due notice shall be given 10
She Department and said Depart
tnent shall have Sticli work Inspect
Ell and certified AZ possible IN tive
same day. cthcrwirs on the next
"s ARTICLE xuL
Reinforced Concrete.