The Detroit times., 1910-10-05

, one "a psr cent Of hosplng = ussd.
the safe Load shall b eompsssd -
foIlows: 4
ssis load On pounds>=sss tAs+
lSAs).
As=n.t e, s, section OF concrete
As=nst cross section OF iono1tuoin-
81 reinforcement.
where columns are subject 20 loads
OF known eccsntricity, the combined
stresses In the extreme nbrs due TO
moment shall not exceed, the maxi
mum compression stress allowed In
slabs and beams.
! The above stresses apply only 10
columns In which the ratio OF the |
unsupported length 90 least side or
diameter does not exceed fifteen
u5).
AIN columns shall have a least
one "a per cent. Of longitudinal re-
enforcement. whether the same 10
used In the calculations or not.
Proper provision shall be made for |
transmitting the stresses at the
splices I'm the column rods. and In
buildings over four ca stories In
height, a proper connection must be
made between the lower and the up
per ends OF the column rods.
less than ten uo) inches in its
smallest dimension.
Sec. 9. BENDING MOMENTS
AND. CONTINUOUS ACTION, The
bending moment for slabs and beams
with uniformly distributed load. ,
shall be taken at y WI
When the slabs and beams are
continuous over both supports. the
bending moment for q uniformly dis.
,,ributsd load shall BE- taken At not
Where slabs and beams are con-
tinuous over one Cd support only. |
the bending moment for q uniformly |
distributed load. shah be taken at
not less than oue-ntnth WI.
,o In the case S.,S OF panels ns
tinuous over all supports. the bend
ing moment OF the slab for a uni |
formly distributed load shall be tax
en- at not less than one-twentieth
w=Load In pounds.
Length OF span In feet.
Length OF span shall always be
understood to be the clear distance
Sec. I. STEEL OVER SUP
PORTS. In all cases where reduc-
lowed on account OF the continuous
action. sufficient reinforcement must
be introduced In the top of the SLAB
or beam over the supports. 10 take
a bending moment equal to the DIFF.
ference between that allowed and
that given for non-continuous men,
bers.
Sec. 3. BEAMS AND ORDERS
TO BE TREATED AS 1T BEAMS.
II the Orders. beams and slabs are
ton. then the sirders and beams
may be treated as 49, beams with
q portion OF the slab as a fiange. In
no case shall the fiange be Of a
greater width than the distance pc
tween adjacent beams. or be as
sumed to extend to q distance on
each side OF the beam, greater than
three 60 times the thickness OF the
slab.
In all cases where the shearing |
stress along the plane OF junction
Of the rib and fange IL excessive,
the beam must be reinforced by
means OF vertical or inclined steel
members crossing well the plane OF
Sec. .. STEEL IN compress
J SION IN TRANSVERSE MEM
BEERS. Where II n necessary TO in
troduce steel to resist compression
pressivs stress allowed on such steel
shall not exceed fifteen Qb) times I
the computed compressive stress In
the concrete at the same distance
from the neutral axis.
Such steel must be thoroughly 1
anchored into the mass OF the con-
crete by means Of stirrups or other
wise to prevent any possibility OF
buckling.
and thermal stresses shall be pro- I
vidsd for by the introduction OF
Sec. II. EXCESSIVE SHEAR.
oped In any part OF a. reinforced
concrete structure, exceed under the
combined loads, the allowed shear
ing stress az fixed herein. q sum-
Client amount Of steel shall be intro
duced In such q position that the
, deficiency in resistance to shear Is
overcome.
Sec. IL. COLUMNS FILLED
!: WITH CONCRETE. Columns built
c1reiy iatticed together by rivetting
and filled In solid and surrounded
with concrete, may be figured as
reinforced concrete columns, using
a stress Of eight hundred $500
closed concrete and twelve thousand
Q2,000) pounds per square inch on
. steel Where reinforced concrete
beams frame into such columns. the
entire end shear shall be taken by
steel brackets or by concrete brack-
cts, properly reinforced. and con-
nected to concrete core Of columns.
: and moulded simultaneously with
Sec. il. PROPORTIONS OF IN
. GRADIENTS. The concrete for
walls, beams. girders and floor con-
struction, shall be mixed In proper
ton by volume. of one % part Port
Land to ,t swo @ pet5' n 81 sana
either broken stone or gravel
The concrete for columns. shall be
mixed In the proportion OF one ID
part Portland cement. one and one
half 1 M Stoks on : :sna a ar sraWs
! In no case shall more than two CD
parts Of sand be used to one I'D part
OF cement.
An mixing shall be done by machine
II the total amount OF concrete ex-
ceeds nifty 800 cubic yards.
The proportions OF the ingredients
must be ascertained by actual meas
3 urement Clean water free from
strong acids or alkaiis must be used
Iron Stag or other similar porous
8 materials, may be used In place or
broken stone or gravel, when ap-
proved by the Department Of Build
men, OF buildings may require .
l reduction in the proportion OF the
Stag or other similar porous ma
3 terial in order to have the voids
properly filled.
Sec. -; oUALITY. OF MATER
3 ing bars used In reinforced con-
4 crete, shall be made by the open
s hearth or the Besssmer process,
6 bars to be rolled directly from the
Z original billet No rerolled steel
3 viii be allowed. The steel shall
3 conform to the following limits In
o chemical composition:
Phosphorus shall not exceed 10
Der cent.
Z Sulphur shall not exceed per cent
Maganese shall not exceed so per
cent.
8 Carbon shall not exceed so per cent.
Z All steel shall conform TO the fol-
8 lowing physical requirements:
. The ultimate tensile strength