The Detroit times. [volume] (Detroit, Mich.) 1903-1920, 1911-02-21


s' I srsssss 2, sE sesfrs.s prss
nected 70 concrete core Of columns.
and moulded simultaneously with
See "a PROPORTIONS or IN
S VAIL. bss,rs .,,1 Tns concrete as for
struction. shall be mixed I'm proper
land cement to two (2l parts OF sand
and not more than four (4) parts Of
either broken stone or gravel
The concrete for columns. shall be
mixed In the proportion OF one I'D
part Portland cement. one and one
half uD parts OF sand and three
CD parts or broken stone or gravel
In no case shall more than two. CD
parts OF sand be used to one Cd part
OF cement ~. :. .t
All mixing shall be done by machine
II the total amount OF concrete ex-
ceeds fifty 900 cubic yards.
The proportions OF the ingredients
must be ascertained by actual meas
strong acids or alkalis must be used
Iron Stag or other similar porous
materials, may be used In place OF
broken stone or gravel, whom ap-
proved by the Department OF Build
ings. and In such cases tho Depart
ment OF Buildings may require a
reduction In the proportion ~ the
Stag or other similar porous ma
terial In .order TO have tho 2oids
ton by volume. OF one ID part Port
Sec L. QUALITY OF MATER
IALS. (a) STEEL. AL reinforc-
ing bars used IN reinforced con.
crete. shall be made by the open
hearth or the Bsssemsr process.
original billet. No rerolled steel
will be allowed. The steel shall
conform to the following limits In
chemical composition
PHOSPHORUS shall not exceed 10
Sulphur shall not exceed .o6 per cent
Manganese shall not exceed so per
cent
All steel shall conform to the fol-
lowing physical requirements:
The ultimate tensile strength
shall not be less than sixty thous-
and (60.000) pounds per square
inch of net cross section.
The yield point shall not be
less than one-half th) the uiu-
The eions alton per cent, in eight
(s) inches shall not be less than
1,400, 600 ultimate strength. with
modification as follows: For each
increase OF one-eighth I'd inch In
inches, a deduction OF one "a per
cent; for each decrease OF one-six-
teenth U-16) inch in thickness, be-
low five-sixteenths (5-16D inch. a
deduction OF two and one-half
fest specimens for bending shall
be bent cold around a diameter
equal to their least thickness. TO
tho following angles without frac-
ture on the outside of the bent por-
ton:
For specimens one CD inch thick.
For specimens quarter (&)
inch thick. 80 degrees.
For specimens one-half NJ inch
thick, ITO degrees
fG inch sP tsieR iso SSs esrsss A
For specimens three sixteenths
(s-16) inch thick. 140 degrees.
For specimens one-eighth thD
inch inch thi ssh;r lso degrees s por,,.ra
e.@. s c shal s 70 the sr stan
dsrd specifcations OF the American
Society for Testing Materials. In
force Dec. 1. 1910. except that the
minimum requirements for tensile
strength shall be as noted In Sec
tion rs of this article.
Co SAND. The sand shall be
clean. free from any organic mat
ter and graded from coarse to- fine.
(d) STONE. GRAVEL OR STAG:
The stone shall be clean crushed
stone, free from dirt or dust and
The gravel shall be washed
The Stag shall be clean crushed
blast furnace Stag. ~
All aggregate must be OF auoh
size as will pass through three
quarter ca inch screen and be re-
tanned on a one-auarter (hy Inch
screen. hHtUig v - t.4..}
Sec, Is. MATERIALS PRoHIB-
TIED. The following materials
shall not be used In reinforcsd con
plaster of paris. sulphate OF lime
and ell similar injurious materials.
Sec, 16, cBNTERING AND
concrete shall be built on centers
All forms shall be built strong.
unyielding, plumb ana true. thor
oughly braccd and with tight
joints, so that no appreciable part
and they shall be supported to
carry all OF the usual loads which
may come upon them without
spring or detection.
For columns an opening shall be
left at the bottom OF the form. for
The opening shall not be closed
until the column Ia to be poured.
Columns over fourteen (14) feet
in height, and under eighteen t1O
inches square, shall have an Inter-
mediate opening or pocket and the
pouring started therefrom. The
forms shall be thoroughly cleaned
Immediately before the concrete Is
poured. and all chips. Ice and other
foreign matters removed.
Before removing the shores un-
der any beam or girder. the column
supporting II shall be stripped, 50
that the column may be examined
on all sides.
the full weight of the floor. column
forms may be removed as soon as
the concrete has set up hard. pro-
vided that the said forms shall not
be removed within seventy-two CID
hours after pouring.
The sides OF girder and beam
forms. may be removed at the ex-
piration Of six (6) days after pour
ing.
fore removing the shores under the
girders and beams. VIII vary with
the design and the conditions OF
the weather. but In no case shall
they be removed In less than three
az b wes sRsp slisr rpS essrn oor slabs
shall not be removed In less time
than ten (10) days after pouring,
but this clause IL not intended to
prevent removing the joists and
tagging within less time, provid-
shored up.
Sec. II. PLACING OF REIN
FORCEMENTS All reinforcing
members shall be accurately locat-
ed In the forms and secured firmly
against displacement. They shall
have a protection OF concrete. not
less than two CD inches thick for
columns, one and one-half (1h
inches thick on the bottom and
side OF Orders and beams and
quarters (A) inch on bottom
OF floor slabs. -
The amount OF concrete protec-
ton shall be clear OF the reinforc-
ing members
Exposed metal centering or ex.
he CON aidered N factor I'm tho