The Detroit times., 1911-02-20

In calculations for wind bracing.
the working stresses may be In
creased by twenty-five t2s) per
Section IL. should new methods
OF construction be desired such as
are not now embodied I'm this or
dinance, such new methods shall
be submitted TO the Department OF
Buildings with full plans. speein.,
these are approved by the Depart
ment. then a full size unit OF the
construction. such as Will be used
In the proposed building and con-
sisting OF all supporting members.
shall be erected and tested 20 the
satisfaction OF the Department. III
In the opinion of the Department
a factor OF safety OF. at least. four
structlon proposed may be APP
proved"
ARTICLE xI.
Floor and Roof Loads.
Sec. I. MINIMUM LIVE LOADS
REQUIRED. Every floor shall be
OF sufficient strength TO bear safely
the weight TO be imposed thereon
In addition TO the weight OF the ma
terial OF which the moor Is construct
ed.
The live loads shall consist OF all
loads other than the dead loads.
The dead loads In all buildings
and structures. shall consist OF the
actual weight OF walls. floors. roofs,
partitions and all permanent con-
Each floor shall be constructed to
carry the following minimum live
loads I'm pounds per square foot uni
formly distributed:
Class !. Store Buildings. Light
First floor. las pounds: all other
floors. 100 pounds: store buildings,
heavy merchandise, It's pounds:
storage buildings. heavy merchan-
disc; 200 pounds; manufacturing and
garages and stables. e Sou pounds. large
buildings. carrying heavy or fast
running machinery, shall be increased
In strength over the above require
ments.
orrice buildings. first moor. 1875
pounds; all other floors. rs pounds.
Glass 2. Hotels. Tenements. Board
ing and Lodging Houses:
First floor. so pounds; Hobbies,
other public rooms. so pounds; pri-
vate rooms and apartments so
pounds: public buildings, first floor,
l26 pounds; all other floors. 90
pounds.
Class 3.
stables and garages, so pounds.
Glass 4. Assembly Halls, Church
es and Church Houses
With fixed seats, 80 pounds; with
movable seats. 100 pounds; floors for
dancing. 126 pounds: stairways. 1875
pounds; Hobbies and passa geways,
400 pounds.
Schools:
Assembly halls. 100 pounds; class
rooms. rs pounds: halls and CORR
doris. 30 pounds; stairways. 100
pounds.
All other buildings in this class:
First floor. 100 pounds, all other
floors. 80 pounds
Class s. Theatres:
With fixed seats: so pounds: with
ways. l25 pounds: lobbies and pas
sageways, 100 pounds.
Attics when not used for habita-
ton, 20 pounds; roofs. 40 pounds;
sidewalks. ESQ pounds.
LOAD. In calculating the load on
footings, walls, piers, and columns
In buildings over three CD stories
In height the following reduction
or the live load OF all floors eek
cept the top or upper floor and the
roof will be allowed.
For warehouses and factories.
seventy -hve t76) per cent. of the
;. For stores and buildings for
light manufacturing purposes.
seventy t7O per cent. Of the live
For churches. school houses
seventy (7o) per cent. of the live
In ONCE buildings. hotels,
hoS anart% logging houses houses:
= and stables. sixty ls6J per cent
OF the live load.
Variation from the above re-
quirements may be had only on
special and written permission
Sec. 8. LOADING OF FLOORS
AND BEAMS. All wooden floor
Ing between two CD toists or sup
p,91rrtso s. or non any floor arch Of brick
or aImored concrete. or other NIL
Ing between two I'D supporting
1oists. beams or girders. shall be
proportioned to carry not less
load. than assumed for such joists,
beams or girders
All beams. rafters. 1oists or
girders,. shall be proportioned to
ton to the whole of the imposed
uniformity distributed live load.
Sec. 4. FLOOR LOAD PLA-
CARDS DISPLAYED. II shall be
snG H4y Of 81 sE s G"as already q 'S csn
structed. or hereafter to be con-
structed, or OF his agent or OF the
occupant OF the building. to pro-
vide. afix and display conspicu-
ing, a placard stating the load per
square foot OF floor space which
may with safety be applied TO that
particular floor, and II the
any floor varies. then there shall
varying part Of such noor.
II shall be unlawful TO
I psTt any tSere cgeh to oors or sr.a sny
extent than the load indicated up
on such placards. 1t shall be the
duty OF the occupants of the
building to maintain such pla-
the premises, and the owner of
the building or his agent shall
cause. the same. to. be properly
affixed with each change Of oc-
puestion. shsii Be Ssrisd sn and fI ap-
buildings before they are atrxed
upon the respective floors of the
different buildings.
ARTICLE XII.
Structural Iron and steel Construc-
ton.
STANDARDS. See Article TX.
Sec. 2. PHYSICAL AND CHEM
ICAL PROPERTIES. See Article
TX, Section 16.
Sec. 8. FRAMING OF sTRUC-
Sec. 4. FACTOR OF SAFETY.
See Article X. Section 3.
Sec. s. UNIT STRESSES. In
all calculations for iron and steel,
the following maximum stresses
will be allowed for safe carrying
capacity:
Medium steel in tension 49,
OF its yield point and never ex-
ceeding 10000 pounds per square
inch, net section,