The Detroit times., 1910-12-07

tiou, tho highest grades OF Port
land cement shall be used. IL shall
be tof uniform consistency and or
such hneness that not more than
ten O0 per cent will be rejected
by sieve OF twenty-five thousand
t25,000) neshes per square inch.
and In add tion IL shall be capable
OF sustaining without rupture
tensile stress OF at least six hun
dred t6OO) pounds per square inch
after one (ll day In air and TWEEN
ty-seven CID days In water. and
all cement shall he subjected TO
such other physical or chemical
tests as may be required In this
Sec. 3. MoRrARs. ca Lime
part fresh lime and not more than
four D parts of sand.
OBJ Cement mortar shall he
made from one Cd part cement
and not more than three go parts
co Cement and lime mortar
shall be made with equal parts OF
cement and lime. and not more
than three CD parts Of sand TO
each whole part OF cement and
Sec. 10. PROPORTIONS OF
CONCRETE. The proportions OF
materials for concrete used In
footings. foundations. walls and re-
tanning walls shall be AS follows:
Not less than one part of cement
TO three CD parts OF sand. and i've
90 parts OF either broken stone
mixed with the proper proportions
or clean water.
In quantities OF over nifty (so)
cubic yards. the concrete Is to be
machine mixed,
An concrete shall be used imme-
diateiy after mixing. and the ma
terials shall be mixed by measure
Sec; II. PORTLAND CEMENT
BRICKS: Portland cement bricks
same dimensions as common brick.
may be substituted. except COR
walls. piers and buttresses sustain
Ing heavy weights. provided said
Portland cement brick shall con
form 10 the tests for materials pre-
scribed In this Ordinance
sec. IL. ARTIFICIAL STONE.
Artificial stone made or Portland
cement and incombustible and
waterproof material. may be used
as substitute for any natural
stone. But no artificial stone CON
tanning more than fifteen G5) per
cent or lime or crushed limestone.
snail be used as Intel or bearing
part OF any building over four ca
stories high.
Artificial stone must conform to
the tests for materials prescribed
Sec. IS. WROUGHT IRON. All
wrought Iron shall be tibrous
tough and ductile. uniform I'm char
acter and having an ultimate ten
forty,cisht thousand t4s.oo0)
pounds per square inch with a
?ieiu point or commercial elastic
limit or twenty-siN thousand (26,-
wv, pounds and an elongation OF
lshteen (ls) per cent in eight 80
, inches. including fracture when
tested in small specimens.
Sec. a. CAST IRON Except
where chilled iron Is specified. all
castings shall be tough grey iron,
free from injurious cold shuts or
blow holes. true To pattern and
having an ultimate tensile strength
or not less than sixteen thousand
tl6.OOo pounds per square inch
Sample pieces one UD Inch
square. cast from the same heat OF
metal in sand moulds. shall be
capable OF sustaining on clear
span OK four Cd feet and eight go
inches. center load OF five nun
dred tSO0) pounds when tested in
the rough bar.
Sec. 10. steel. CASTINGS. steel
castings shall be made by the open
ncarth or crucible process and shall
be free from injuries. and blow
, holes and shall have the following
minimum requirements:
All steel castings shall be an
nealed.
Sample bars to develop at least
; an ultimate strength or seventy
thousand t7O.do0) pounds per
square inch, with a yield point or
commercial elastic limit OF thirty
one thousand five hundred (3l. 5000
pounds per square inch and an
elongatIon OF eighteen Gs) per
. cent In two go inches. Including
fracture and :eductlo OF twenty
hve (2o) per cent In area.
Sec. is. STRUCTURAL STEEL
. All structural steel including rivets.
shah have their physical and chem
teal properties in accordance with
, the Manufacturers Standard Steel
specifications, as revised to Febru-
AIRY o., 1903. and rs found in the
hand books OF steel manufacturers.
Sec. IL TESTS. The Depart
ment OF Buildings may require, at
any time, certified copies OF full
inspection from recognized experts,
; FOR any or all materials used in
buildings OF Types and and no
such materials shall be concealed
or built upon, until the Depart
ment or Buildings. upon their re-
quest. shall have been furnished
with satisfactory proof that such
materials and workmanship are
fully equal TO the standard
Sec. IS. NEW MATERIALS. Be-
fore any new materials not here
tofore employed are used as CON
str.ctlonal parts or buildings or
structures. permission must be OBJ
Buildings who shall apply such
tests to the said new materials rs
: may be- necessary to determine the
strength and durability OF such
materials.
ARTICLE Y.
Calculation or STRESSES
Section /. CALCULATION Oh
CONSTRUCTION The stresses OF
8 materials hereafter used in the
construction Of buildings or struc-
lures. shall be the calculated
stresses due to the dead load"
plus the live load"
The allowable factors or units OF
safety, or the dimensions OF each
piece or combination OF materials
required In a building or structure,
shall be ascertained by computa-
tion according to this ordinance.
See. 2 TEST OF FRAMES.
When Il test OF any framed struc-
ture Is required to ascertain its
physical strength or It's resistance
To fire, frost or water, such tost
shall be made with full finished
sizes. and similar exposure as
their proposed use In the building
requires. and when the condition
for such tests are not established
I'm thus Ordinance, the method OF
the authorities prescribed In The
previous sections shall be followed