The Detroit times., 1911-02-23


the working stresses may be In
cent.
Section IL. should new methods
are not now embodied In this orr
dinance, such new methods shall
be submitted TO the Department OF
Buildings with full plans. specih-
cations and calculations. and IL
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-
sistinE of all supporting members.
satisfaction of the Department IL
In the opinion OF the Department
factor of safety OF, at least, four
CD shall be developed. the con-
s srnnata proposed may be APP
ARTICLE NJ.
Floor and Roof Loads.
Sec. I. MINIMUM LIVE LOADS
REQUIRED. Every moor shall be
the weight to be Imposed thereon
In addition TO the weight or the ma
terial OF which the floor II construct
ed. ,a,
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-
struction.
Each moor shall be constructed to
carry the following minimum live
loads In pounds per square foot uni
formly distributed:
Class I. Store Buildings, Light
Merchandise:
First floor. l2s pounds: all other
heavy merchandise. ITS pounds:
storage buildings, heavy merchah-
disc, zoo pounds; manufacturing and
light storage. $50 pounds: large
garages and stables. SO pounds
The floors Of manufacturing
running machinery. shall be Increased
In strength over the above require
ments.
office buildings. first moor. 125
pounds; all other floors, 76 pounds.
Glass g. Hotels. Tenements, Board
ing and Lodging Houses:
First floor, 80 pounds; Hobbies,
halls, corridors. dining rooms and
other public rooms, so pounds; pri-
vate rooms and apartments, so
125 pounds; all other floors. 90
pounds.
Class 3.
Residences. so pounds; small
stables and garages. so pounds
Class Z: Assembly Halls. Church
With fixed seats, so pounds; with
movable seats. 100 pounds: floors for
dancing. 125 pounds; stairw1ys. 1875
pounds; Hobbies and passageways.
100 pounds
Assembly halls, 100 pounds; class
rooms. rs pounds; halls and corri-
doris. 80 pounds; stairways, 100
pounds.
All other buildings in this class:
First floor. 100 pounds; all other
floors. so pounds.
Class S. Theatres:
With fixed seats. 80 pounds: WITH
movable seats. 100 pounds; stair
ways. 125 pounds; Hobbies and pas
sageways, 100 pounds.
Attics when not used for habita-
ton. 20 pounds; roofs, 40 pounds;
Sidewalks. ESQ pounds.
Sec. 2. REDUCTION OF LIVE
LOAD. In calculating the load on
in buildings over Pt three any es) 01 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.tiv t7O per cent of the
For stores and buildings for
seVenty 1aoS nsr ssn ss x
sss wv Pof Seht. u eho Nv
For churches, school houses
and places OF public amusement,
seventy (7o) per cent. Of the live
In ONCE buildings. hotels.
dwellings. apartment houses
Tenement houses. lodging houses
and stables. sixty 600 per cent
Variation from the above re-
quirements may be had only on
special and written permission
from the department Of buildings
ing between two CD joists or sup
ports. or any floor arch Of brick,
tile or concrete, or any reinforced
or armored concrete, or other NIL
5os Set bssms s on siTaer. sus sRRo ss
proportioned to carry not less
than ten (10) per cent. more live
load. than assumed for such Joists,
beams or gtrders
girders,. shall be proportioned to
carry all of the dead load In addi-
ton to the whole OF the imposed
uniformity sfo di a., nng I've losd.
CARDS DISPLAYED. It shall be
building OF class I, already con-
structed. or hereafter to be CON-
Of the i sa afsn or to OF p foe
vide, affix and display conspicu-
ously on each floor Of such build
ing. placard stating the load per
square ,, foot OF, OF floor space which Which
strength OF the different parts of
any floor varies, then there shall
be such placards for each
fT Il shall part be OF un issa n0V e.
load any such doors or any
extent than the load indicated up
S on such pi ;ss .,o, It shall Be the
building to maintain such pla-
cards during their occupancy OF
the premises. and the owner OF
the building or his agent shall
afixed with each change Of oc-
cupancy. These placards and COM
putations shall be verified and APP
proved by the department. OF
upon the respective floors Of the
different buildings,
ARTICLE XII.
Structural Iron and steel Construc-
=, Sec !. e. !, NJ, IRON AND STEEL
Sections Is. j. and is. e a.
Sec. q. PHYSICAL AND CHEM
ICAL PROPERTIES. See Article
Sec. 3. FRAMING of sTRuc-
TURES. See Article X. Section q
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 45%
OF Its yield point and never ex-
ceedine 10000 pounds per square
inch, net section.
Medium steel in shear 10000
mounds per souara inch net sac