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


In calculations for wind bracing.
the working stresses may be In
creased by twenty-five tzb) per
cent
Section Ia should new methods
OF construction be desired such as
dinance. such new methods shall
be submitted to the Department OF
Buildings with fun plans. specin-
cations and calculations. and IL
msnt. then a full size unit OK the
construction. such as win be used
In the proposed building and con-
sisting OF all supporting members.
shall be erected and tested TO the
satisfaction or the Department. IL
IN the opinion OF the Department
a factor OF safety OF, at least, four
(D shall be developed. the con-
struction proposed may be APP
ARTICLE HI.
Floor and Roof Loads.
Sec. 1. MINIMUM LIVE LOADS
REQUIRED. Every floor shall be
Of sufficient strength TO bear safely
in addition 70 the weight OF the ma
teriai OF which the floor Is construct
ed.
The live loads shall consist OF all
loads other than the dead loads.
The dead loads In all buildings
atto otihNtttNos ohoAt COioiot Vi lno
actual weight OF walls. floors. roofs,
partitions and all permanent con-
struction.
Each floor shall be constructed 10
carry the following minimum live
loads In pounds per square foot uni
Class !. Store Buildings. Light
Merchandise:
First floor, las pounds: all other
foors, 100 pounds: store buildings.
heavy merchandise. ITS pounds;
disc. zoo pounds; manufacturing and
garages and stables. SO pounds.
The floors OF manufacturing
buildings, carrying heavy or fast
running machinery. shall be increased
In strength over the above require
Office buildings. first floor, 125
pounds; all other floors, rs pounds.
Glass 2. Hotels. Tenements, Board
ing and Lodging Houses:
ha conr HST 50 dn Roand Room. 0Sp,s Sa
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.
Residences, SO pounds; small
stables and garages, so pounds.
Class 4. Assembly Halls. Church
es and Church Houses:
With fixed seats, 80 pounds; with
movable seats. 100 pounds; floors for
dancing. 125 pounds; stairways, 1875
pounds; Hobbies and passageways.
400 pounds.
Schools:
Assembly halls. 100 pounds; class
rooms, rs pounds: halls and corri-
doris. 30 pounds; stairways. 100
All other buildings In this class:
First floor. 100 pounds; all other
floors. 80 pounds.
Class s. Theatres:
With fixed seats. 80 pounds; with
movable seats. 100 pounds; stair
sageways, loo pounds.
General:
Attics when not used for habita-
ton. 20 pounds; roofs. 40 pounds;
sidewalks. $50 pounds.
Sec g. REDUCTION OF LIVE
LOAD. In calculating the load on
footfngs, walls. piers, and columns
In buildings over three ca stories
In height. the following reduction
or the live load OF all floors lex
eept the top or upper floor and the
For warehouses and factories,
seventy 1--WE 76) per cent. OF the
For stores and buildings for
seventy I7o) per cent. of the live
load.
For churches, school houses
and places OF public amusement.
seventy (7o) per cent Of the live
In ONCE buiidings. hotels.
tenement houses. lodging houses
and stables. sixty (6O per cent
Variation from the above re-
quirements may be had only on
special and written permission
from the department. OF buildings
See Sec. 8 LoADIMG OF FLOORS
ing between two CD joists or sup
ports. or any floor arch OF brick,
tile or concrete, or any reinforced
or aImored concrete, or other NIL
jos,s Det Sssms on sSasrs us sRRol bs
proportional to carry not less
than ten (10) per cent. more live
load, than assumed for such joists.
beams or girders.
Orders. shall be propcrtioned to
carry all of the dead load In add
ton to the whole of the imposed
uniformity distributed live load.
CARDS DISPLAYED. Il shall be
building OF class I, already con-
structed. or hereafter to be con-
structed, or. Of his agent or of the
vide. afix and display conspicu-
ously on each floor of such build
ing, a placard stating the load per
square foot of floor space which
may with safety be applied to that
Strength of the different parts of
any floor varies, then there shall
be such placards for each
varying :, part of n such u, ho0r;
load ' any .u Oh n Sorswl or an ~
extent than et the load Indicated up
on such placards. 1t shall be the
duty OF the occupants OF the
cards during their occupancy Of
the premises. and the owner. OF
the building or his agent shall
cause the same. to. be properly
affixed with each change Of oc-
putations shall be verified and APP
Bu building. befors s they SsgA are af,1sd
upon the respective floors Of the
different buildings.
ARTICLE XII.
Structural Iron and steel Construc-
STANDARDS. See Article TX.
Sections Is. Il and is.
Sec. 2. PHYSICAL AND CHEM
ICAL PROPERTIES. See Article
TX. Section Is.
Sec. 8. FRAMING OF sTRUC-
TURES. See Article X. Section o
Sec. 4. FACTOR OF SAFETY.
See Article X, Section g.
Sec. 5. UNIT STRESSES. In
all calculations for iron and steel,
the following maximum stresses
will be allowed for safe carrying
capacity;
Medium steel In tension ASH
of It's yield point and never ex-
ceeding $4,000 pounds per square