Workmanship in the fabrication, preparation
and installation of materials shall conform to generally accepted
good practice
A.
Protection at excavations. Until provision for permanent
support has been made, excavations shall be properly guarded and protected
so as to prevent the same from becoming dangerous to life or limb
and shall be sheetpiled and braced, where necessary, by the person
causing she excavation to be made to prevent adjoining earth from
caving in.
B.
Excavations of ten feet or less. When an excavation
extends not more than 10 feet below the curb level, the owner of a
structure, the safety of which may be affected by such excavation,
shall preserve and protect the same from injury and, when necessary,
shall underpin and support the same by proper foundation, and for
such purpose he shall be permitted, if necessary, to enter upon the
premises where such excavation is being made.
C.
Excavations more than 10 feet deep. When an excavation
extends more than 10 feet below the curb level, he person causing
such excavation to be made shall, if afforded the necessary license
to enter upon adjoining land, at his own expense, preserve and protect
from injury every structure, the safety of which may be affected by
such excavations and, when necessary, shall underpin and support the
same by proper foundations, irrespective of the depth to which the
foundations of such structure may extend. If the necessary license
is not accorded to the person making the excavation, then it shall
be the duty of the owner refusing such license to preserve and protect
such structure from injury and, when necessary, to underpin and support
the same by proper foundations, and for that purpose shall, if necessary,
be permitted to enter upon the premises where such excavation is being
made.
D.
Support of party walls. In case there is a party wall
along a lot line of the premises where an excavation is being made,
the person causing the excavation to be made shall, at his own expense,
preserve such party wall in as safe a condition as it was before the
excavation was commenced and shall, when necessary, underpin and support
the same by proper foundation.
E.
Curb level. In case a structure is so located that
the curb level to which it is properly referred is at a higher level
than the curb level to which the excavation is referred, such part
of any necessary underpinning or foundation as may be due to the difference
in the curb levels shall be made and maintained at the joint expense
of the owners of the adjoining premises at that point.
F.
Superintendent of Buildings may act. If the person
whose duty it shall be under the provisions of this code to properly
guard and protect an excavation or to prevent adjoining earth from
caving in or to preserve or protect any wall or structure from injury
shall neglect or fail so to do after having had twenty-four-hours
notice from the Superintendent of Buildings, such Superintendent may
enter upon the premises and employ such labor and furnish such materials
and take such steps as, in his judgment. may be necessary to prevent
adjoining earth from caving in or to make such wall or structure safe
and secure or to prevent the same from becoming unsafe or dangerous
at the expense of the person whose duty it is to keep the same safe
and secure. The Village or any person doing said work or any part
thereof under and by direction of the Superintendent of Buildings
may bring and maintain an action against the person last herein referred
to to recover the value of the work done and materials furnished in
and about said premises in the same manner as if he had been employed
to do the work by said person.
G.
Abandoned excavations. Whenever an excavation is made
and the structure to be erected thereon has not been begun within
60 days and the excavation lacks a foundation wall of sufficient strength
to retain the surrounding earth or the place is dangerous for any
other reason such as lack of proper backfill, the excavation shall
be considered abandoned. Such abandoned excavation may be ordered
filled by the service of notice by the Superintendent of Buildings
upon the owner of the plot upon which it is located in person or by
mail to his latest known address as it appears on the Village tax
rolls. If, thereafter, the owner fails to have the excavation filled
within the time specified in the notice or within a reasonable time
if no time is specified in the notice, the excavation may be filled
by the Village and the cost thereof assessed against the property
as a tax lien thereon after due notice to the owner and hearing as
to the reasonableness of the cost thereof.
A.
General requirements. Foundation walls, except those
erected upon solid rock or upon wharves or piers on the waterfront
and except those of dwellings or two-and-one half-story buildings
of frame construction, shall be carried not less than four feet below
the adjacent ground level and shall rest on solid ground or on level
surface of rock or on files or ranging timbers when solid rock is
not found. The foundation walls of dwellings or two-and-one-half-story
frame buildings may be stopped at a depth of three feet below grade.
B.
Footings.
(1)
Materials. Footings consisting of stone, concrete,
reinforced concrete or steel grillages shall be provided under foundation
walls that rest on earth. Footings of wood, when permitted by the
Superintendent of Buildings, may be used if they are entirely below
permanent water level.
(2)
Steel grillage footings. When steel grillage beams
are used, they shall be provided with separators and bolts and shall
rest on a proper concrete bed and shall be completely encased in concrete.
(3)
Protection of metal. Where metal is incorporated in
or forms part of a foundation, it shall be protected from rust by
paint, asphalt, concrete or by such materials and in such manner as
may be approved by the Superintendent of Buildings.
(4)
Pressure under footings. For the loads exerting pressure
under the footings of foundation walls, the full dead loads and the
assumed live loads from all floors on the lowest tier of columns,
piers or walls shall be taken.
(5)
Design. Footings shall be so designed that the pressure
they produce on the soil per unit of area shall be uniform as far
as possible under all parts of the foundation walls, and such pressures
shall not exceed the bearing capacity of the soil. In proportioning
the areas of footings, the dead loads alone shall be considered; provided,
however, that in no case shall the full dead loads, plus the reduced
live loads exceed the bearing capacity of the soil.
C.
Pile foundations.
(1)
Resistance and method of driving.
(a)
Piles which are to be used to sustain all of
a structure or any part thereof shall be driven to a resistance satisfactory
to the Superintendent of Buildings by such methods as will not impair
their strength and as will ensure the retention of that resistance.
(b)
Piles shall be held in correct location during
driving. No load shall be permitted upon a pile broken prior to or
during driving. If any pile is driven out of plumb more than 2% of
the pile length, the design of the foundation shall be modified to
support lateral forces properly and additional piles shall be driven
if necessary.
(2)
Loads on piles.
(a)
The following formula may be used as an approximate
indication of the allowable load on any pile not driven to rock, except
that in no case shall the maximum allowable loads for the various
types of piles be exceeded.
|
For drop hammers:
|
(a) No. 1.tif.png) | |
|
For single-acting hammers:
|
(a) No. 2.tif.png) | |
|
Where
| ||
|
P = the allowable load on the pile in pounds.
| ||
|
W = the weight of the striking part of the hammer
in pounds.
| ||
|
H = the fall, in feet, of the striking part
of the hammer.
| ||
|
S = the average penetration, in inches, under
the last five blows after the pile has been driven to a point where
successive blows produce equal penetration.
| ||
(b)
When a double-acting steam hammer is used in
which steam or compressed air is employed to increase the blow of
the driving ram, the term "W" shall be equal to the weight of the
driving ram, plus the area of the piston multiplied by the mean effective
pressure of the steam or compressed air on the piston during the stroke,
but "W" shall not exceed the total weight of the hammer.
(3)
Tests of sustaining of power of piles. Where any doubt
exists as to the safe sustaining power of the piles, the Superintendent
of Buildings may order loading tests of individual piles or groups
of piles to be made at the expense of the owner of the proposed structure
or of the person causing the piles to be driven. Tests shall be made
with 150% of the proposed load and shall be considered unsatisfactory
and the result unacceptable, if, after standing 24 hours, the total
net settlement after deducting rebound is more than 0.01 inch per
ton of total test load. The record of every test shall be filed with
the Department.
(4)
Jetting of piles. Exterior jetting of piles shall
be permitted only by special permission of the Superintendent of Buildings.
If conditions require jetting, such conditions shall be fully set
forth in the application and such permission requested. If jetting
is used, it shall be carried out in such a manner that the carrying
capacities of piles already in place shall be unimpaired.
(5)
Wood piles.
(a)
Wood piles shall be of dense or sound grade
southern pine, structural or common grade douglas fir, spruce, mixed
hardwoods or other species approved for such use. Piles shall be of
sound timber and free from wind shakes, short or reversed bends. They
shall be cut above the ground swell, shall have a reasonably uniform
taper and shall be so straight that a line between the center of the
point and the center of the butt shall not depart from the body of
the pile more than 1% of the length of the pile. The least diameter
at the point of the pile shall be six inches. The least diameter of
the butt of a pile shall be 12 inches, except that where a pile is
less than 25 feet in length, it may be 10 inches or more in diameter.
Measurements shall be taken under the bark. The minimum total penetration
of any pile shall be 12 feet.
(b)
Piles, other than those used as foundations
for wood frame structures over submerged or marsh lands, shall be
cut off below permanent water level. Piles used as foundations for
wood frame structures over submerged or marsh lands shall be impregnated
with creosote or other preservative as approved by the Superintendent.
(c)
The maximum allowable load on a wood pile having
a six-inch point shall be 15 tons and on a pile having a point of
eight inches or over 20 tons.
(d)
Nothing in this section shall prohibit the use
of piles with a butt at least eight inches in diameter when, in the
opinion of the Superintendent of Buildings, such is adequate, in the
case of a light private dwelling.
(6)
Concrete filled steel piles.
(a)
Piles consisting of concrete steel tubes shall have a minimum inside diameter of 10 inches and a shell thickness of at least 3/8 inch, except that ten-and-twelve-inch piles may have a shell thickness of 5/16 inch. The concrete shall be of a mixture at least equal to reinforced concrete as specified in § 86-47D(3). The ends of each tube shall be perpendicular to its axis, and all bearing surfaces shall be smooth and true-cut by an approved method. Splices shall be of such material and design as to assure good alignment of tubes. If splices below the upper splice are closer together than 20 feet, a 5% reduction in load values shall be made for each additional splice used.
(b)
Where the borings indicate that piles will be
less than 60 feet in length, the maximum designed outside diameter
of the tube shall be at least 1/40 of the length. If, as actually
driven, such piles exceed 40 diameters in length, a one-percent reduction
in load shall be made for each diameter of excess length. Where borings
indicate that the piles will be 60 feet or more in length, the minimum
diameter shall be 18 inches and the minimum shell thickness shall
be 1/2 inch, and no reduction from the allowable loading need be made
for the slenderness ratio.
(c)
After driving, the inside of the tube shall
be cleaned of any foreign matter before placing the concrete filling.
When tubes exceed 50 diameters in length, the concrete in the tube
below the upper 50 diameters shall be deposited with a tremie or fully
lowered bottom-dump bucket. The concrete shall never be placed through
water except on specific written approval of the Superintendent of
Buildings after submission of the detailed method of procedure.
(d)
The allowance load on any such pile when driven
to bedrock shall not exceed 500 pounds per square inch on the concrete
and 7,500 pounds per square inch on the steel, provided that in computing
the effective area of the steel, the outer 1/16 inch of thickness
shall be deducted from the thickness of the tube. When driven open-ended
to refusal in boulders or a mixture of gravel and boulders with no
softer material underlying, the maximum unit loads shall be 50% of
the above values. Piles so used shall be spaced at least 20 inches,
plus the diameter of the tube.
(7)
Piles cast in place.
(a)
Concrete piles cast in place shall be so made and placed as to ensure the exclusion of any foreign matter and to ensure a continuous and full size pile. Piles shall be driven in such order and with such spacing as to ensure against distortion or injury to the finished pile. Concrete shall be of a mixture at least equal to reinforced concrete, as specified in § 86-47D(3), and shall be placed in the dry and shall not be placed in a form containing water. The average diameter of such piles shall be at least 11 inches, and the diameter of the point shall be at least eight inches.
(b)
The maximum load for cast-in-place piles shall
be 30 tons. When not driven to rock or hardpan, their carrying capacities
shall be determined by test.
(8)
Precast concrete piles.
(a)
Concrete piles moulded and cured before driving
shall be designed and reinforced to permit handling and driving them
without injury. Reinforcing steel shall be so located that it will
be covered by at least two inches of concrete. The diameter or least
lateral dimension of such piles shall be 10 inches or more at the
point and shall average at least 12 inches throughout the length of
the pile for piles up to 20 feet, 14 inches for piles up to 30 feet
and 15 inches for piles up to 40 feet. For piles over 40 feet in length,
the diameter or least lateral dimension shall be 1/35 of the length,
except that all piles shall be at least 15 inches and shall not be
required to exceed 24 inches in diameter or least lateral dimension.
(b)
The concrete shall be of a mixture at least equal to reinforced concrete as specified in § 86-47D(3).
(c)
Piles shall be reinforced with longitudinal
reinforcing at least equal to 2% of the volume of the concrete in
the pile, together with lateral reinforcing in the form of hoops or
spirals, at least one-fourth-inch round rods or wire, spaced 12 inches
on centers throughout the length of the pile, except the bottom and
top three feet where this spacing shall be reduced to three inches.
(d)
The maximum allowable load, in tons, shall not
exceed two times the average diameter or least lateral dimension in
inches, but shall not exceed 40 tons in any case. The center-to-center
spacing of piles shall be one inch per ton of load, but not less than
30 inches. Average penetration shall be at least 10 feet.
A.
Materials. Foundation walls shall be built of approved
masonry, reinforced concrete or steel encased in masonry, provided
that no hollow blocks of burnt clay shall be used unless they are
vitrified or are salt-glazed, except for surfaces in contact with
mortar.
B.
Thickness.
(1)
Foundation walls shall be of adequate strength and
thickness to resist lateral pressures from adjacent earth and to support
their vertical loads and shall be at least of the same thickness as
the wall next above.
(2)
If built of rubble stone, the thickness shall not
be less than 18 inches. If built of brick, concrete or hollow building
blocks, the thickness shall be not less than 12 inches, provided that
when such walls for dwellings do not extend more than five feet below
adjacent ground level, the minimum thickness shall be eight inches.
A.
Construction. Walls built to retain or support adjoining
earth or rock shall be constructed of approved masonry or reinforced
concrete of adequate strength and stability.
B.
Hydraulic head. Unless provision is made to drain
off water, a hydrostatic pressure, due to a head equal to the height
of the wall, shall be assumed.
A.
Materials. Approved masonry shall be constructed of
brick, stone, concrete or hollow building blocks or a combination
of these materials as provided in this article.
B.
Protection against freezing. Unless adequate precautions
against freezing are taken, no masonry shall be built when the temperature
is below 28° F. on a rising temperature or 32° F. on a falling
temperature at the point where work is in progress. The use of any
frozen material or building upon any frozen masonry or frozen soil
is forbidden.
C.
Erection of walls and piers.
(1)
In each story, the walls shall be carried up full
thickness to the top of the beams above.
(2)
Except when carried independently by girders at each
floor, no wall shall be built up more than two stories in advance
of any other portions of the walls of the buildings.
(3)
All walls that meet or intersect shall be adequately
bonded or anchored. Piers having less than four square feet of cross
section, when located at an intersection with a wall, shall be bonded
into and built as part of that wall.
D.
Piers.
(1)
Every pier supporting a girder, arch or column or
a lintel carrying a wall over an opening of more than 10 feet shall
be built of approved masonry.
(2)
Isolated piers shall not exceed, in height, 10 times
their least dimension and, if built of brick, shall be so bonded as
approved by the Superintendent of Buildings.
E.
Arches and lintels.
(1)
Openings in walls shall be spanned by a lintel or
arch of incombustible materials.
(2)
Where steel or reinforced masonry lintels are used,
they shall be of such strength that the maximum deflection is 1/360
of the clear span and shall have at least five inches of bearing on
each end and shall rest upon solid bearing.
(3)
Lintels of manufactured or natural stone shall be
of sufficient strength to carry the superimposed load without deflection.
(4)
Masonry mullions less than 12 inches in width on either
face of the wall shall be suitably reinforced or doweled if of stone.
(5)
Masonry arches shall have at least one-inch rise for
each foot of span and shall be so designed as to carry the superimposed
load. Proper provision shall be made for resisting lateral thrust.
F.
Timber in walls.
(1)
No timber, except nailing blocks not exceeding an
ordinary brick in size, shall be placed in masonry walls, provided
that in nonfireproof construction, timber lintels may be placed over
openings on the inside of the wall, resting at each end not more than
two inches on the wall and chamfered or cut to serve as centers for
rowlock or keyed arches.
(2)
No masonry shall be supported on wood girders or other
form of wood construction.
G.
Bracing during construction. The walls and beams of
every structure during erection or alteration shall be strongly braced
from the beams of each story and, when required, shall also be braced
from the outside until the structure is enclosed.
H.
Anchorage of masonry walls.
(1)
Masonry walls shall be anchored to each tier of joists
or beams bearing on them, at maximum intervals of four feet, by metal
anchors having a minimum cross section of 1/4 inch by 1 1/4 inches
and at least 16 inches long, securely fastened to the joists or beams
and provided with split and upset ends or other approved means for
building into masonry.
(2)
Masonry walls parallel to joists or beams shall be
provided with similar anchors, at maximum intervals of six feet, engaging
three joists or beams. Girders shall be similarly anchored at their
bearings. Upset and T-ends on anchors shall develop the full strength
of the anchor strap.
I.
Brick masonry.
(1)
Bonding of solid masonry walls. In solid brick walls
there shall be the equivalent of at least one full header course for
each six courses of each wall surface. Where facing brick is used
of a different thickness from the brick used for backing, the courses
of the facing brick and backing shall be brought to a level at least
once in each six courses in the height of the backing, and the facing
brick shall be properly tied to the backing by a full header course
of the facing brick or other approved method. Facing brick shall be
laid at the same time as the backing. In walls more than 12 inches
thick, the inner joints of header courses shall be covered with another
header course which shall break joints with the courses below.
(2)
Wetting of brick. All brick having an appreciable
absorption shall be thoroughly wet before laying.
(3)
Joints in solid masonry walls. All horizontal and
vertical joints in brick masonry shall be filled with mortar.
J.
Stone masonry. Stone masonry walls shall be anchored as specified in § 86-60H, except that anchors for bearing walls shall be at least three feet long and at least 1/4 inch by two inches in section. All stone shall be laid in cement or cement-lime mortar, and all joints and spaces shall be thoroughly filled. Natural stone shall be laid in the masonry on its natural bed. Rubble stone walls shall be at least four inches thicker than required for solid bearing walls and shall not be used in structures over 60 feet high.
K.
Construction of hollow walls.
(1)
Hollow block walls.
(a)
Where walls of hollow building blocks are decreased
in thickness, the blocks in the top course of the thicker wall shall
be filled solidly with concrete or covered with slabs of hardburned
terra cotta or concrete at least one inch in thickness.
(b)
Terra cotta, concrete or steel templates of
approved size and thickness shall be placed under all floor beams
and girders to properly distribute the loads.
(c)
In walls built only one unit in thickness, each
unit shall break joints with those next above. When more than one
unit is required to produce a given wall thickness, the units shall
break joints with the units next above and shall be laid with a masonry
bond equivalent to one course of headers to each course of stretchers.
(d)
For nonbearing interior partitions of one story
or less in height and constructed of units to be left exposed on one
or both sides for architectural effect, these bonding requirements
may be waived.
(e)
Hollow block walls shall be anchored as specified in Subsection H, except that all anchors shall be galvanized or of noncorroding metal.
(f)
Where hollow units are set with the cells horizontal,
they shall be set in a full bed of mortar 1/2 inch or less in thickness
and with vertical joints buttered full on shells and webs. Where hollow
units are set with the cells vertical, the bearing members shall be
buttered and vertical joints slushed full of mortar.
(2)
Hollow walls of solid masonry units. At points where wall thicknesses decrease in hollow walls of solid masonry units, a course of solid masonry shall be interposed between the wall section below such point and that next above. Anchorage requirements shall be the same as for hollow block walls. Other construction requirements shall conform with Subsection I.
(3)
Limitation of hollow walls. Hollow walls of brick
or walls of hollow block shall not be used as bearing walls in structures
exceeding 40 feet or three stories in height and, except in buildings
of one story in height or of frame construction, shall not be used
as party walls.
L.
Ashlar facing.
(1)
Stone, architectural terra cotta or other approved
material used for the facing of a wall shall have a thickness of not
less than 1/8 of the height of the unit, but in no case less than
3 3/4 inches.
(2)
Facings of brick or solid structural units shall be
bonded into the backing with headers or stretchers at least four inches
thicker than the facing, the equivalent of 1/6 of the area of the
wall.
(3)
Stone ashlar facing shall have at least 20% of the
superficial area not less than four inches thicker than the remainder
of the facing to form bond stones, which shall be uniformly disposed
in the wall.
(4)
In stone ashlar, every stone that is not a bond stone
and every stone that projects wholly or partly beyond the face of
the wall shall be securely anchored to the backing with at least one
noncorroding metal anchor at least 3/16 inch by one inch or the equivalent
in cross-sectional area.
(5)
Faced walls shall be at least as thick as required
for masonry walls of the material forming the backing.
M.
Veneer.
(1)
Masonry veneer shall consist of bricks, stone, concrete,
terra cotta, hollow building blocks or other approved material.
(2)
Such veneer shall rest directly upon a foundation
wall or upon other approved masonry or reinforced concrete or steel.
(3)
It shall be securely attached with noncorroding ties
at intervals of not more than 16 inches vertically and 24 inches horizontally
to the wall or, in the case of frame construction, to approved sheathing
combined with a weatherproof lining.
(4)
Flashing to prevent moisture from penetrating behind
the veneer shall be provided at wall openings. All wood sills must
be protected by weatherproof lining or flashing.
(5)
In all cases, the veneering shall be excluded in calculating
the bearing wall thickness and the required thickness of the wall.
The maximum height of veneering on walls, other than panel or enclosure
walls, shall be 40 feet above the foundations.
N.
Stucco.
(1)
Stucco for frame construction shall consist of cement
mortar on expanded metal lath weighing not less than 3 4/10 pounds
per square yard or on woven or welded wire lath not lighter than No.
19 gauge.
(2)
Stucco shall be kept at least eight inches above adjacent
ground surfaces.
(3)
Flashing to prevent moisture from penetrating behind
the stucco shall be provided at wall openings.
O.
Mortar.
(1)
In masonry construction, no mortar other than cement
mortar shall be used in footings, foundation walls or rubble stone
walls.
(2)
No mortar, other than cement mortar or cement-lime
mortar, shall be used in hollow walls of brick, hollow building block
masonry, chimneys, backing of walls faced with ashlar, exterior walls
in skeleton construction, curtain walls, parapet walls, isolated piers
or linings of existing walls.
P.
Wall thickness.
(1)
Thickness of solid bearing walls.
(a)
The thickness, in inches, of solid masonry bearing
walls for the respective story heights, except in private dwellings
35 feet or legs in height and except as otherwise provided in this
subsection, shall be at least:
|
8
|
12
| |||||||
|
7
|
12
|
12
| ||||||
|
6
|
12
|
12
|
12
| |||||
|
5
|
12
|
12
|
12
|
12
| ||||
|
4
|
16
|
12
|
12
|
12
|
12
| |||
|
3
|
16
|
16
|
12
|
12
|
12
|
8
| ||
|
2
|
16
|
16
|
16
|
12
|
12
|
12
|
8
| |
|
1
|
20
|
16
|
16
|
16
|
12
|
12
|
12
|
8
|
|
Stories
|
8
|
7
|
6
|
5
|
4
|
3
|
2
|
1
|
(b)
For calculation of wall thicknesses, 13 feet
shall be assumed as the maximum height of a story.
(c)
No twelve-inch wall shall exceed four stores
of 55 feet in height.
(d)
When the clear span between bearing walls or
between a bearing wall and an intermediate support is more than 26
feet, much wall shall be increased four inches in thickness for each
12 1/2 feet or fraction thereof that such span is in excess of
twenty.six feet, except where such bearing walls are adequately reinforced
by buttresses.
(2)
Thickness of interior walls in residence structures.
(a)
The thickness, in inches, of interior bearing
walls, with bearing on both sides, in residence structures for the
respective story heights shall be at least:
|
6
|
8
| |||||
|
5
|
8
|
8
| ||||
|
4
|
8
|
8
|
8
| |||
|
3
|
8
|
8
|
8
|
8
| ||
|
2
|
12
|
8
|
8
|
8
|
8
| |
|
1
|
12
|
12
|
8
|
8
|
8
|
8
|
|
Stories
|
6
|
5
|
4
|
3
|
2
|
1
|
(b)
Where interior walls in residence structures
have bearing on one side only or are nonbearing, the required thickness,
in inches, shall be eight inches for the uppermost 55 feet of wail
height and 12 inches below the fifty-five foot distance from the top
of the wall, provided that no eight-inch wall shall be over five stories
in height.
(c)
Where wood floor and roof beams bear on both
sides, such beams shall be staggered on the bearing wall and there
shall be at least three inches of masonry between any two such wood
beams.
(d)
The maximum length of such bearing and non-bearing
walls between cross walls, cross bracing, piers or buttresses shall
be 30 feet.
(3)
Solid masonry walls above roof levels. Solid masonry
walls above roof levels, 12 feet or less in height, enclosing stairways,
elevator shafts, penthouses or bulkheads shall be at least eight inches
thick and may be considered as neither increasing the height nor requiring
any increase in the thickness of the wall below, provided that the
allowable working stress requirements are met.
(4)
Solid masonry walls for private dwellings. In any
private dwelling, bearing walls of brick, including party walls, may
be eight inches in thickness, provided that such dwellings are not
more than 35 feet in height and that the eight-inch walls do not exceed
50 feet in length between cross walls or adequate buttresses, except
that when the walls are not pierced by openings of any kind, such
length may be 60 feet.
(5)
Eight-inch solid masonry walls.
(a)
In one-story buildings, the walls may be eight
inches in thickness, provided that no such wall shall exceed 50 feet
in length between cross walls or adequate buttresses.
(b)
Outside of the fire limits, buildings not exceeding
30 feet or two stories in height, the walls of which under this code
could be of frame construction, may be eight inches in thickness,
provided that no such wall shall exceed 50 feet in length between
cross walls or adequate buttresses.
(c)
When the clear span between bearing walls or
between a bearing wall and an intermediate support is more than 26
feet, such wall shall be increased four inches in thickness for each
12 1/2 feet or fraction thereof that such span is in excess of
26 feet, except where such walls are adequately reinforced by buttresses.
(6)
Increased thickness of masonry walls.
(a)
The thickness of masonry walls shall conform to the provisions of this subsection and shall in all cases, irrespective of other requirements of this section, be sufficient to keep the stresses in the masonry within the working stresses prescribed in § 86-53.
(b)
The maximum percentage of openings in any horizontal
section of bearing wall shall be 50% of the gross sectional area when
cement mortar is used and 35% when other mortars are used, except
upon the following conditions: that the thickness of the wall be increased
four inches for each 15% or fraction thereof of increased opening
area in excess of 50% or 35% respectively, and, in all cases, the
total percentage of openings shall be less than 75% or the horizontal
sectional area of the wall.
(c)
The total thickness of any wall whose thickness
is increased in accordance with the requirements of this section shall
be governed by that requirement producing the maximum thickness.
(7)
Bracing of masonry walls. Masonry walls in structures,
except as otherwise provided in this subsection, shall be braced either
horizontally or vertically at right angles to the wall face at maximum
intervals of 20 times the wall thickness. Horizontal bracing may be
obtained by floors or roofs. Vertical bracing may be obtained by cross
walls, wall columns or buttresses or by increasing the wall thickness.
(8)
Masonry walls in skeleton construction.
(a)
Panel walls of masonry in skeleton frame structures
shall be at least eight inches thick if constructed of solid masonry
or at least 12 inches thick if constructed of hollow masonry or at
least 10 inches thick if constructed of a combination of hollow and
solid masonry, except that spandrel and apron walls may be eight inches
thick or may be of materials or of assemblies of materials other than
masonry meeting the requirements of this article. Combinations of
hollow and solid masonry shall be constructed with at least four inches
of solid masonry on the exterior face. The maximum height between
supports of such walls when constructed of these minimum thicknesses
shall be 13 feet. When such walls exceed 13 feet in height, they shall
be increased two inches in thickness for each 6 1/2 feet or fraction
thereof.
(b)
Panel walls shall be bonded or otherwise so
secured to the structure as to furnish adequate lateral support to
the wall.
(c)
Exterior nonbearing enclosure walls anchored
to columns, piers or floors, but not built between columns or piers
nor wholly supported at each story in skeleton construction, shall
meet all the requirements for height, thickness and type of construction
required for bearing walls.
(9)
Masonry curtain walls.
(a)
Curtain walls of solid masonry shall be at least
eight inches thick for the uppermost 13 feet and at least 12 inches
thick for the next 52 feet or fraction thereof below and shall be
increased in thickness four inches for each succeeding 60 feet or
fraction thereof below.
(b)
When built of masonry, other than solid masonry,
they shall be at least 10 inches thick for the first 13 feet, 12 inches
thick for the next lower 39 feet and shall be increased four inches
in thickness for each 39 feet or fraction thereof next below, provided
that the maximum horizontal distance between lateral supports shall
be 20 feet. When the distance between the lateral supports exceeds
20 feet, the thicknesses of all walls specified in this section shall
be increased four inches for each additional 10 feet or fraction thereof
between lateral supports. Curtain walls of hollow masonry 12 inches
or more in thickness shall be made of at least two bonded units.
(10)
Thickness of hollow bearing walls.
(a)
Bearing walls of hollow block masonry in structures
not exceeding 40 feet or three stories in height, except as hereinafter
provided, shall be not less than 10 inches in thickness for the uppermost
20 feet of their height and 12 inches in thickness below that.
(b)
When hollow walls of solid masonry units are
used as bearing walls in structures not exceeding 40 feet or three
stories in height, they shall be not less than eight inches in thickness
for the uppermost 10 feet of their height and 12 inches in thickness
below that.
(c)
In any private dwelling, hollow bearing walls not less than eight inches in thickness may be used in place of solid masonry bearing walls as specified in Subsection P(4).
Q.
Existing walls.
(1)
Use of existing walls. Walls heretofore built, whose
thickness at the time of their erection was in accordance with the
requirements of the then existing laws but which are not in accordance
with the requirements of this article, may be used without change,
if in good condition, in buildings hereafter erected or altered, provided
that the stresses in the masonry do not exceed the working stresses
prescribed by this code and the height of such walls is not increased,
except insofar as may be necessary to make the height uniform.
(2)
Lining of walls. In case it is desired to use and
increase the height of an existing wall, which is less in thickness
than required by this code, such wall shall be reinforced by a lining
of brickwork so that the combined thickness with the old wall shall
be not less than four inches more than the thickness required for
a new wall corresponding with the total height of the wall when increased
in height, provided that such lining shall not be used to a greater
height than 40 feet, and that such wall shall not be increased to
exceed 75 feet in height. Such lining shall be supported on proper
foundations and shall be not less than eight inches in thickness and
thoroughly anchored to the old wall with suitable anchors placed two
feet apart and properly fastened or driven into the old wall in rows
alternating vertically and horizontally with each other, the old wall
being first cleaned of plaster or other coating where any lining is
to be built against the same. No wall, however, shall be lined, unless
in good condition, and not until the approval of the Superintendent
of Buildings has been given.
R.
Parapet walls.
(1)
Every open area of any roof permitted to be used by
occupants for any purpose and every area of a roof used as a means
of exit shall be protected, in a manner approved by the Superintendent
of Buildings, by a parapet wall or a guardrail not less than three
feet six inches in height above the level of such area.
(2)
Exterior or division walls of masonry, other than
fire walls, over 15 feet high in nonfireproof structures shall have
parapet walls carried two feet above the roof, except in residence
structures and detached structures with overhanging roofs or where
such walls are to be finished with cornices or gutters.
(3)
Parapet walls shall be of the same thickness as the
wall below, except that in no case shall a thickness of more than
12 inches be required.
(4)
Residence structures shall have parapet walls carried
at least two feet above the roof with the following exceptions:
(a)
Parapet walls between structures of the same
height and 40 feet or less in height shall extend at least eight inches
above the roof.
(b)
Party walls in structures, the roofs of which
pitch at an angle of 30° or more from the horizontal, may stop
at the top of the roof boards, provided that no combustible material
passes through the wall and that the junction of roof and wall is
thoroughly fire-stopped.
(c)
Fire partition walls for the purpose of subdividing
nonfireproof residence structures may be carried to the bottom of
the roof boards and thoroughly grouted with cement mortar.
(5)
When parapet walls function as parts of party or fire
walls, they shall conform to the requirements for such walls.
S.
Chases and recesses.
(1)
Chases in eight-inch walls or within the required
area of any pier are prohibited. The maximum depth of any permitted
chase in any wall shall be 1/3 of the wall thickness. The maximum
length of any horizontal chase without suitable structural support
shall be four feet, and the maximum horizontal projection of any diagonal
chase shall be four feet.
(2)
Recesses shall have at least eight inches of material
at the back.
(3)
The maximum aggregate area of recesses and chases
in any wall shall be 1/4 of the whole area of the face of the wall
in any story, except that for stairs, elevators and dumbwaiters, the
walls, including foundation walls behind such facilities, may be reduced
to 12 inches.
(4)
Chases or recesses in fire walls, fire partitions
and in fire protection of structural members, which would reduce the
thickness below the minimum specified in this code, are prohibited.
(5)
Chases and recesses may be built into hollow walls
and walls constructed of hollow block or tile, but the cutting of
chases or recesses in walls of these types of construction is prohibited.
A.
Basis of designs. The design of reinforced concrete
members shall be based on the generally accepted theory of flexure
as applied to reinforced concrete and shall be in accordance with
the requirements of this code.
B.
Span length.
(1)
The span length of freely supported beams and slabs
shall be the clear span, plus the effective depth of beam or slab,
but shall not exceed the distance between centers of the supports.
(2)
The span length for continuous or restrained beams
built to act integrally with supports shall be the clear distance
between faces of supports.
(3)
For continuous or restrained beams having brackets
to act integrally with both beam and support and at least as wide
as the beam and making an angle of 45° or more with the horizontal,
the span shall be measured from the section where the combined depth
of the beam and bracket is at least 1/3 more than the depth of the
beam. No portion of such a bracket shall be considered as adding to
the effective depth of the beam. Brackets making an angle of less
than 45° with the horizontal may be considered as increasing the
effective depth of the beam, but not as decreasing the span length.
(4)
Maximum negative moments are to be considered as existing
at the ends of the span as defined above.
C.
Depth of beams or slabs and minimum thickness of slabs.
(1)
The effective depth of the beam or slab shall be taken
as the distance from the centroid of the tensile reinforcement to
the top surface of the structural slab.
(2)
The minimum thickness of reinforced concrete floor slabs shall be 3 1/2 inches or four inches when finished monolithically, and roof slabs shall be at least 3 1/2 inches thick, except as specified in Subsection E.
(3)
The minimum thickness of reinforced concrete for mansard
roofs, dormers, roofs of bulkheads and all roofs having a slope of
more than 30° from the horizontal shall be three inches.
(4)
Topping of approved incombustible materials may be
included in the minimum thickness required for fire resistance of
slabs.
D.
T-beams. In T-beam construction, the slab shall be
built integrally with the beam. The effective flange width of symmetrical
T-beams shall not exceed 1/4 of the span length of the beam, and its
overhanging width on either side of the web shall not exceed eight
times the thickness of the slab nor 1/2 the clear distance to the
next beam.
E.
Ribbed floor construction.
(1)
Ribbed floor construction includes floor systems with
slabs and ribs placed monolithically between permanent or removable
fillers in which the ribs are spaced 30 inches or less from face to
face. The ribs shall be straight, at least four inches in width and
of a maximum clear depth of three times the average width.
(2)
When concrete or scored burnt clay tile is used, the
thickness of the slab shall be at least 1/12 of the clear distance
between the ribs with a minimum of 1 1/2 inches. Where such tile
is of strength at least equal to that of concrete and the joints are
staggered, the shells in contact with the concrete may be included
in the resisting sections. In two-way construction, provided that
the tile filler is completely surrounded by concrete ribs as specified,
the exterior shells of the tile in contact with the concrete may be
used for strength calculations for shear and bending, and where the
top slab is not required for strength, such top slabs may be omitted,
provided that the construction is protected by at least two inches
of incombustible material.
(3)
When removable forms or fillers not complying with
the requirements of the preceding paragraph are used, the thickness
of the slab shall be at least 1/10 of the maximum clear distance between
the ribs with a minimum thickness of three inches in structures where
the minimum required live load is 60 pounds per square foot or less
and 3 1/2 inches where the minimum required live load exceeds
60 pounds per square foot. Where the underside of the floor construction
is protected by a ceiling of metal lath and plaster at least 7/8 inch
thick, these thicknesses may be decreased by one inch.
(4)
Conduits or pipes shall not be buried in the slab,
except where expressly permitted by the Superintendent of Buildings,
and in such latter cases under the following conditions only: where
the slab contains conduits or pipes, the thickness shall be at least
one inch, plus the total overall depth of such conduits or pipes at
any point. Such conduits or pipes shall be so placed as not to reduce
the strength of the construction.
F.
Shrinkage and temperature reinforcement. Reinforcement
for shrinkage and temperature stresses normal to the principal reinforcement
shall be provided in floor and roof slabs where the principal reinforcement
extends in one direction only. Such reinforcement shall be spaced
at most 18 inches in floors and 12 inches in roofs. The area, per
foot of width, shall be at least 0.073 square inches for floors and
0.11 square inches for roofs.
G.
Types of web reinforcement.
(1)
Web reinforcement may consist of any one of the following
types or any combination of them:
H.
Spacing of stirrups. Where the shearing stress of
any section is equal to or less than S5 and greater than S4, the maximum
distance between two consecutive stirrups, measured normal to the
direction of stirrups, shall be 3/4d, and when the shearing stress
exceeds S5, the maximum distance between two consecutive stirrups,
measured normal to the direction of stirrups, shall be 3/8d.
I.
Anchorage of web reinforcement.
(1)
Web reinforcement shall be anchored at both ends by one of the following methods or a combination of them, but only anchorage meeting the requirements of Subsection I(1)(a), (b) or (c) shall be used for shearing stresses in excess of S5.
(2)
The end anchorage of a web member not bearing on the
longitudinal reinforcement shall be such as to engage an amount of
concrete sufficient to prevent the bar from pulling out. In all cases,
the stirrups shall be carried as close to the upper and lower surfaces
as fireproofing requirements permit.
(3)
The stress in a stirrup or web reinforcement bar shall
be less than a value equal to the surface area of the bar embedded
within the upper or lower 1/2 of the beam multiplied by S10 for plain
bars or S11 for deformed bars, except that when wire fabric is used
for web reinforcement, it shall have welded intersections at maximum
intervals of six inches, but, in any case, the maximum stress shall
be 16,000 pounds per square inch.
J.
Reinforced concrete columns.
(1)
Limiting dimensions. Principal reinforced columns
in buildings shall have a minimum total thickness of 12 inches. Posts
that are noncontinuous from story to story shall have a minimum total
thickness of six inches.
(2)
Unsupported length of columns.
(a)
The unsupported length of reinforced concrete
columns shall be taken:
[1]
In flat slab construction, as the clear distance
between the floor and underside of the capital.
[2]
In beam and slab construction, as the clear
distance between the floor and the underside of the shallowest beam
framing into the column at the next higher floor level.
[3]
In floor construction with beams in one direction
only, as the clear distance between floor slabs.
(b)
When reinforced concrete brackets are used at
the junction of beams or struts with columns, the clear distance between
supports may be considered as reduced by the depth of the bracket,
provided that the width of the bracket is at least equal to that of
the beam and at least 1/2 of the column.
(3)
Columns with longitudinal and spiral reinforcement.
(a)
The permissible axial load (P) on columns reinforced
with longitudinal bars and closely spaced spiral hooping enclosing
a circular core shall be determined by the following formula:
|
P = Ac fc (1 plus 15p plus 50p')
| |
|
where
| |
|
fc does not exceed S15 or, in any case, 850
pounds.
| |
|
Ac = area of core of spirally-hooped column
measured to the outside diameter of the spiral.
| |
|
p = ratio of effective area of longitudinal
reinforcement to the area of concrete core.
| |
|
p' = ratio of volume of lateral reinforcement
to the volume of concrete core.
|
(b)
The minimum longitudinal reinforcement shall
be 0.0075 of the gross area of the column, and the maximum longitudinal
reinforcement shall be 0.04 of the gross area of the column. The minimum
volume of spiral reinforcement shall be twenty-five hundredths of
the volume of vertical reinforcement but, in any case, at least 0.005
at most 0.02 of the volume of the core.
(c)
The spiral reinforcement shall consist of cold-drawn
steel wire having a maximum diameter of 5/8 inch. The minimum clear
space between wires shall be one inch.
(d)
The value of P shall be within the value Ag
2fc, where Ag equals gross area of reinforced concrete.
(4)
Columns with longitudinal reinforcement.
(a)
The permissible axial load (P) on columns reinforced
with longitudinal bars and separate lateral ties shall be determined
by the formula:
|
P = fc Ag (1 plus npg)
| |
|
where
| |
|
fc does not exceed S15.
| |
|
Ag = gross area of reinforced concrete.
| |
|
pg = ratio of longitudinal reinforcement to
the gross area of columns.
|
(b)
The minimum longitudinal reinforcement shall
be 0.005 of the gross area of the column, and the maximum longitudinal
reinforcement shall be 0.04 of the gross area of the column. The longitudinal
reinforcement shall consist of at least four bars having a minimum
diameter of 5/8 inch.
(c)
Lateral ties at least 1/4 inch in diameter shall
be spaced at vertical intervals of at most 15 times the diameter of
the vertical reinforcement with a maximum of 12 inches. Crossties
shall be provided for the vertical reinforcement at maximum intervals
equal to the minimum column dimension but at least 12 inches and at
most 24 inches in any case. The total cross-sectional area of lateral
and crossties per foot of length of column shall be at least one-fifteenth
of the area of the vertical reinforcement.
(5)
Bending in reinforced concrete columns. Bending stresses
in all columns should be computed on the basis of loading conditions
and end restraint. Columns shall be designed for the bending moments
developed by unequally loaded panels, eccentric loads, etc., and the
concrete and steel areas shall be increased so that the maximum unit
stresses shall not exceed the allowable working stresses.
(6)
Composite columns. The permissible load on composite
columns in which structural steel columns are thoroughly encased in
concrete, reinforced with between 1/2% and 4% of longitudinal steel
and between 1/2% and 2% of spiral reinforcement, shall be determined
as follows:
(a)
The steel core shall be between four and 25%
of the gross area of the column.
(b)
Loads carried by the steel core shall be transferred
to it by positive structural means consisting of billets or brackets.
(c)
The unit stress on the steel section shall be
within 16,000 pounds per square inch.
(d)
The (d).tif.SM.png)
ratio unsupported length of columns divided by the least radius
of gyration, shall be within 120.
(d).tif.png)
ratio unsupported length of columns divided by the least radius
of gyration, shall be within 120.(e)
The diameter of the concrete core, measured
outside of the spiral, shall be at least 16 inches.
(f)
The structural steel column shall be at least
three inches from the inside of the spiral at any point.
(g)
The steel column shall be solid or of the open-section
type.
(h)
The net area of concrete, bounded by the outside of the spiral, shall be at least that required to carry the total floor load of one or more stories above at a unit stress within: fc (1 plus 15p plus 50p') and the same load shall not stress the entire area of concrete beyond a unit stress equal to 2 fc. See § 86-61J(6)(j).
(i)
The entire load carried by the steel and concrete
shall not create an average unit stress on an area, equal to the total
area of concrete, plus the steel section, times (n), greater than
2 fc.
(j)
The entire load carried by the steel and concrete
shall not create an average unit stress on an area, equal to the area
of concrete bounded by the outside of the spiral, plus the steel section,
times (n), greater than: fc (1 plus 15p plus 50p').
(7)
Transfer or stress at base of columns. The comprehensive
stress in longitudinal reinforcement at the base of a column shall
be transferred to the pedestal or footing by dowels. There shall be
at least one dowel for each column bar, and the total sectional area
of the dowels shall be at least the sectional area of the longitudinal
reinforcement in the column, The dowels shall extend into the column
and into the pedestal or footing at least 30 diameters of the dowels
for plain bars or 24 diameters for deformed bars.
K.
Reinforced concrete walls.
(1)
The minimum thickness of reinforced concrete bearing
walls shall be 1/25 of the unsupported height but at least eight inches.
Approved buttresses, built-in columns or piers designed to carry all
vertical loads may be used in place of greater thickness. The allowable
working stress in compression in such walls shall be within those
established by the column formulas.
(2)
Bearing walls shall be reinforced with an area of
steel in each direction, vertical and horizontal, at least equal to
0.0025 of the cross-sectional area. Walls more than eight inches thick
shall have 1/2 the steel at each face of the wall. The maximum spacing
of the bars shall be 18 inches in either direction. Reinforcement
shall be at least 3/8 inch in diameter. The vertical steel shall not
be relied on to carry load unless arranged and tied as in reinforced
concrete columns.
(3)
In buildings of skeleton construction, reinforced
concrete walls, when supported at each story, shall be at least eight
inches thick. Such walls shall be reinforced in the same manner as
bearing walls.
L.
Inspection of controlled concrete. When concrete structures are designed as provided in § 86-53C(3), Controlled concrete, all concrete work shall be inspected by the architect or engineer responsible for its design. A record shall be kept of such inspection, which shall cover the quality and quantity of concrete materials, including water, the mixing and placing of the concrete and the placing of the reinforcing steel. The inspection record shall also include a complete record of the progress of the work and of the temperatures, when these fall below 50° F., and of the protection given to the concrete while curing. These records shall be available for inspection by the Superintendent of Buildings at all times during the progress of the work and shall be preserved for two years after the acceptance of the structure.
M.
Load tests.
(1)
The Superintendent of Buildings may order the test
under load of any portion of a completed reinforced concrete structure
when there is any doubt as to the stability of the structure. The
minimum age of any concrete construction which may be subjected to
such tests shall be 60 days.
(2)
In such tests, the member or portion of the structure
under consideration shall be subjected to a superimposed load equal
to 1 1/2 times the live load, plus 1/2 of the dead load. This
load shall be left in position for a period of 24 hours before removal.
If, during the test. evidence of weakness develops in any portion
of the structure, such changes or modifications shall be made as are
necessary to make the structure adequate for the rated capacity or,
where lawful, a lower rating shall be established. The structure will
have passed the test if the total deflection does not exceed the deflection
computed by accepted formulas. When the total deflection exceeds the
computed deflection, the structure will have failed to pass the test
if, within 24 hours after the removal of the load, it recovers less
than 75% of the maximum deflection shown during the 24 hours while
under load.
N.
Mixing of concrete.
(1)
The fine and coarse aggregates shall be measured separately,
and the proportion of fine to coarse aggregate shall be such as to
produce concrete that will work readily around the reinforcement without
excess puddling or spading. The ratio of fine to coarse aggregate
by weight shall be at least 1/2 and at most two.
(2)
The proportions shall be such as to prevent segregation
of the materials during transportation and placing and to prevent
the collection of an appreciable amount of water on the surface of
the concrete in place.
(3)
The amount of coarse material shall be such as to
eliminate harshness in placing or honeycombing in the structure. When
forms are removed, the faces and comers of the members shall show
smooth and sound throughout.
(4)
The methods of measuring and mixing concrete materials
shall be such that the proportions of fine and coarse aggregate to
cement and water to cement ratio can be accurately controlled during
the progress of the work and easily checked at any time by the Superintendent
of Buildings.
(5)
The concrete shall be mixed until there is a uniform
distribution of the materials and the mass is uniform in color and
homogeneous.
O.
Field tests of concrete.
(1)
During the progress of the work, a reasonable number
of compression tests shall be made as required by the Superintendent
of Buildings, and at least one specimen shall be tested for each 100
cubic yards of concrete of any one strength. The test cylinder shall
be made and stored in accordance with the Standard Method of Making
and Storing Compression Test Specimens of Concrete in the Field, D,
C31-31 of the American Society for Testing Materials, and tested at
the age of 28 days.
P.
Placing, curing and depositing concrete.
(1)
Concrete shall be handled from the mixer to the place
of final deposit as rapidly as practicable by methods which will prevent
the separation or loss of the ingredients. The deposition of partially
hardened concrete is prohibited.
(2)
When concreting is once started, it shall be carried on as a continuous operation until the placing of the section or panel is completed. Where construction joints are necessary, they shall be made in accordance with Subsection S, Construction joints.
(3)
Concrete shall be kept moist for a period of at least
seven days after being deposited.
(4)
The deposition of concrete which has a temperature
less than 50° F. is prohibited, and the concrete shall be maintained
at a temperature of at least 50° F. for not less than 72 hours
or until thoroughly hardened.
Q.
Forms and details of reinforced concrete construction.
(1)
Design of forms. Forms shall conform to the shape,
lines and dimensions of the member as called for on the plans. They
shall be substantial and sufficiently tight to prevent leakage of
mortar, and they shall be properly braced or tied together so as to
maintain position and shape and ensure safety to workmen and passersby.
Temporary openings shall be provided, where necessary, to facilitate
cleaning and inspection immediately before depositing concrete.
(2)
Removal of forms. The removal of forms shall be carried
out in such a manner as to ensure the complete safety of the structure.
Where the structure as a whole is supported on shores, beam and girder
sides, column and similar vertical forms may be removed within 24
hours, provided that the concrete has hardened sufficiently and that
it is uninjured thereby. The supporting forms shall be undisturbed
until the concrete has hardened sufficiently to permit their removal
with safety. Shoring shall be kept in place until the concrete has
acquired sufficient strength to safely support its weight and the
load upon it.
R.
Reinforcement.
(1)
Cleaning and bending reinforcement.
(a)
Metal reinforcement, before being placed, shall
be free from scales of rust or other coatings that will destroy or
reduce the bond. Reinforcement shall be formed to the dimensions indicated
on the plans before it is embedded in the concrete. Cold bends shall
have a radius of at least two times the least dimensions of the bar.
(b)
Metal reinforcement shall not be bent or straightened
in a manner that will injure the material. Heating of reinforcement
for bending is prohibited.
(2)
Placing of reinforcement. Metal reinforcement shall
be accurately placed and secured and shall be supported by concrete
or metal chairs or spacers or metal hangers. The minimum center-to-center
distance between parallel bars shall be 2 1/2 times the diameter
for round bars or three times the side dimension for square bars,
but, in all cases the clear spacing between bars shall be at least
one inch or 1 1/3 times the maximum size of the coarse aggregate.
Bars at the upper face of any member shall be embedded a clear distance
of at least one diameter or at least one inch.
(3)
Splices in reinforcement.
(a)
Splices in column bars shall provide a lap of
at least 24 diameters for deformed bars and 30 diameters for plain
bars.
(b)
When bars in members subject to flexure only
are spliced, they shall be lapped sufficiently to transfer the stress
by bond and shear. Splices at points of maximum stress are prohibited
unless approved by the Superintendent of Buildings.
(4)
Protection of reinforcement.
(a)
Metal reinforcement shall be protected by at
least 3/4 inch of concrete in walls and slabs, 1 1/2 inches in
beams and girders and two inches of columns.
(b)
At those surfaces of footings and other principal
structural members in which the concrete is deposited directly against
the ground, metal reinforcement shall have a minimum covering of three
inches. At other surfaces of concrete exposed to the ground and at
the outside surfaces of exterior walls, columns, girders and beams,
metal reinforcement shall have a minimum covering of two inches, except
stirrups, which shall have a minimum covering of 1 1/2 inches.
S.
Construction joints.
(1)
Joints not indicated on the plans shall be so made
and located as to cause the least impairment of the strength of the
structure. Where a horizontal joint is to be made, any excess water
and laitance shall be removed from the surface after concrete is deposited.
Before depositing of concrete is resumed, the hardened surface shall
be cleaned and roughened and all weak concrete removed.
(2)
At least two hours must elapse after depositing concrete
in the columns or walls before depositing in beams, girders or slabs
supported thereon. Beams, girders, brackets, column capitals and haunches
shall be considered as part of the floor system and shall be placed
monolithically therewith.
(3)
Construction joints in floors shall be located near
the middle of spans of slabs, beams or girders unless a beam intersects
a girder at this point, in which case the joints in the girders shall
be offset a distance equal to twice the width of the beam. In this
last case, provision shall be made for shear by use of inclined reinforcement.
A.
Cast-iron columns.
(1)
Dimensions. Cast-iron columns shall not have a smaller outside diameter or side than five inches nor shall they have an unsupported length greater than that allowed by § 86-53E.
(2)
Thickness of metal. The thickness of metal shall not
be less than 1/12 the diameter or least dimension of cross section
but never less than 3/4 inch. When necessary, the thickness shall
be increased near the end so that the core of the column below a joint
shall not be larger than the core of the column above, in which case
the metal may be tapered down for a distance of not less than six
inches or a joint plate may be inserted of sufficient strength to
distribute the load. Whenever the core of a cast-iron column has shifted
more than 1/4 the thickness of a shell, the thickness of the metal
all around shall be assumed equal to the thinnest part.
(3)
Joints. Cast-iron columns shall be machine faced at
the end to a true surface perpendicular to the axis. They shall be
bolted together with at least four bolts, not less than 3/4 inch in
diameter, passing through the flanges, the bolts being of sufficient
length to allow the nuts to be screwed up tightly; and as each column
is placed in position, the bolts shall also be placed in position
and the nuts shall be screwed up tightly.
(4)
Flanges. Where cast-iron columns rest one on top of
another, the top flange of the lower column shall project on all sides
not less than three inches from the outer surface of the column, and
the shape and dimensions of the bottom flange of the upper column
shall be the same as those of the top flange of the lower column,
except that when a column is placed on a lot line, the flanges on
the side toward such lot line may be omitted if not required for bolting.
Flanges shall be at least one inch in thickness when finished and
reinforced by fillets and brackets when necessary.
(5)
Bolt holes. All holes in cast-iron columns shall be
drilled. The diameter of the holes shall not exceed that of the bolts
by more than 1/16 inch.
(6)
Limitation. Cast-iron columns shall not be used in
any case where the load is so eccentric as to cause tension in the
cast iron nor shall they be used for such parts of the structural
frame of buildings which are required to resist stresses due to wind.
(7)
Inspection. No cast-iron column shall be set in place
until it has passed an inspection satisfactory to the Superintendent
of Buildings. Wherever blowholes or imperfections are found in a cast-iron
column which reduce the area of the cross section at that point more
than 10%, such columns shall be condemned. Cast-iron columns not cast
with one open side or back shall have three-eighths-inch holes drilled
in the shaft to exhibit the thickness of the castings as may be required
by the Superintendent of Buildings. Cast-iron columns shall not be
painted before inspection.
(8)
Cast-iron column bases. All parts of a cast-iron base
or bearing plate shall be at least one inch in thickness.
B.
Cast-iron lintels. Cast-iron lintels shall not be
less than 3/4 inch in thickness at any point and shall not be used
for spans exceeding six feet.
C.
Structural steel.
(1)
Quality and workmanship. The material used in structural
steelwork shall be of uniform quality and free from defects which
would influence the strength or stability of the structure. Workmanship
shall be good and shall conform to the best accepted standards of
practice. Methods of fabrication, transportation and erection shall
be such that the finished structure is free from defects or injuries
which would render it unfit for use or occupancy.
(2)
Design requirements. All steelwork shall be designed to sustain the total imposed dead load, including the weight of the steelwork itself, together with the required live load as specified in this code. Proper provisions shall be made in the design for temporary stresses occurring during erection, for eccentricity of loading and for the influence of live loads producing impact or vibration. In addition to the plans and specifications required by § 86-6, Applications for permits, the applicant shall submit to the Superintendent of Buildings a copy of such computations for the design of the structural steelwork of the proposed structure as the Superintendent requests.
(3)
Eccentric loading. Full provision shall be made for stresses caused by eccentric loading. All columns shall be fully investigated for conditions of loading in the preparation of the design and these conditions shall be reviewed when the erection plans are approved and the location of all framing determined by figures. Where the design is predicated on special details to reduce eccentric conditions, such details shall be illustrated on the design drawings. Eccentric conditions shall be fully considered also in the examination and approval of shop drawings. The column formula given under § 86-53D(2) shall be assumed to produce the maximum allowable extreme fiber stress at the floor line without eccentric loading. Where the bending stress due to eccentric loading exceeds 10% of the working stress in the column under direct load, additional material shall be added to keep this excess within 10%. In all cases of eccentric loading, special attention shall be given in the design to typing columns securely above and below the point of loading at the nearest floor line where it can be done adequately.
(4)
Joints in structural steel. Columns and compression
members, when faced for bearings, shall be spliced sufficiently to
hold the connecting members securely in place. When not faced for
bearing, all splices shall be fully riveted or bolted.
(5)
Structural steel column bases. All bases or shoes
used to distribute column loads to foundations shall be designed to
meet the requirements of this code and may be made as a part of the
columns.
(6)
Structural steel beams and girders. Rolled beams shall be proportioned according to the moment of inertia of their net section. Plate girders, with webs fully spliced for tension and compression, shall be so proportioned that the unit stress of the net section is within the maximum stress, specified in § 86-53D, as determined by the moment of inertia of the net section.
(7)
Flange plates. Flange plates of all riveted girders
shall be limited in width so as not to extend more than six inches
or more than 12 times the thickness of the thinnest plate beyond the
outer row of rivets connecting them to the angles.
(8)
Plate girder webs.
(a)
Plate girder webs shall have a thickness of
at least one 1/160 of the clear distance between flange angles for
medium structural steel and, in any case, at least 1/4 inch.
(b)
Intermediate stiffeners shall be required at
all points where:
(b).tif.png) | |
|
where
| |
|
h = clear distance between flanges in inches.
| |
|
s = greatest unit shear at the point in question,
in pounds per square inch, under any condition of complete or partial
loading.
| |
|
t = thickness of web in inches.
|
(c)
The clear distance between stiffeners, when
stiffeners are required by the foregoing, shall not exceed 72 inches
or that given by the formula:
(c).tif.png) | |
|
where
| |
|
d = clear distance between stiffeners in inches.
|
(9)
Minimum thickness of structural steel framework. For
the main structural framework of structures, all steel used shall
be at least 0.20 inch thick for interior work and at least 0.30 inch
thick for exterior work, except that in residence structures whose
maximum height is 2 1/2 stories or 35 feet above the foundation
wall or supporting framework, a minimum thickness of 0.125 inch shall
be permitted for interior and exterior walls when the vertical members
are spaced a maximum of 24 inches apart, provided that the safe loads
and unsupported lengths specified elsewhere in this code are not exceeded
and that the material used is copper-bearing or other rust-resisting
steel.
(10)
Rivet spacing. The maximum distance between rivets
in the line of stress in compression members shall be 16 times the
thickness of the thinnest outside plate or shape and 20 times the
thickness of the thinnest enclosed plate or shape but in no case to
exceed 12 inches. At right angles to the direction of stress, the
maximum distance between lines of rivets shall be 30 times the thickness
of the thinnest plate or shape. In built sections with angles having
two gauge lines, the maximum distance between centers of rivet holes
in the line of stress in each gauge line shall be 24 times the thickness
of the thinnest plate or shape but never more than 18 inches. The
maximum distance from the center of rivet holes to any edge shall
be 12 times the thickness of the thinnest plate or shape.
(11)
Rivet grips. Rivets carrying calculated stresses and
whose grip exceeds five diameters shall have their number increased
1% for each additional 1/10 inch in the rivet grip. Special care shall
be used in heating and driving such rivets.
(12)
Field riveted and bolted connections.
(a)
In tier structures less than 125 feet high in
which the height is less than 2 1/2 times the minimum horizontal
dimensions, all column splices and field connections may be bolted.
(b)
In structures in which the height is over 100
feet and is more than 2 1/2 times the minimum horizontal dimension
and in structures 100 feet or less in height in which the height is
more than four times the minimum horizontal dimension, column splices
and connections to columns shall be riveted or welded.
(c)
In structures over 125 feet in height and in
all structures of a special character, connections of beams and girders
to columns and beams and girders bracing columns and column splices
shall be riveted. Column splices in tier structures less than 125
feet high, except as provided in the preceding paragraph, may be bolted.
(d)
All other field connections may be bolted, except
that in all structures, the connections for supports for running machinery
or other moving loads shall be riveted or welded.
(e)
Within existing structures, steelwork for alterations
or additions, except to the main structural framework, which do not
affect existing column splices, connections and other riveted work
may be bolted.
(13)
Painting. Steelwork, except that which is to be welded
or to be encased in concrete made of noncorrosive aggregates and noncorroding
alloy steel, shall, before erection, be thoroughly cleaned and given
one coat of acceptable metal protection and well-worked into the joints
and open spaces. After erection, steelwork, except that which is to
be encased in concrete made of noncorrosive aggregates and noncorroding
alloy steel, shall be given an additional coat of acceptable metal
protection of another color. Steel parts for which paint is required
and which are not in contact but inaccessible after assembling shall
be properly protected by paint.
(14)
Protection of structural steel from weather. Exterior
steel columns in walls, which are not protected by glass or similar
materials, shall be protected from the weather by efficient and approved
waterproof material or by at least eight inches of masonry.
(15)
Templates. When any lintel, beam, girder or truss
is supported at either end by a wall or pier, it shall be properly
anchored thereto and shall rest upon a template or shoe of cast iron,
steel or stone of such design and dimensions as to safely distribute
its load on the masonry, except that when beams not exceeding six
inches in depth are placed not more than 30 inches on centers, no
templates shall be required.
(16)
Gas cutting. Gas cutting may be employed in the fabrication
of structural steel members or parts used in building construction
in accordance with rules promulgated by the Superintendent of Buildings.
Gas cutting on any member while it is carrying stress is prohibited.
(17)
Structural steel for stair construction. Steel strings
for interior stairs shall have a minimum thickness of 3/16 inch. Material
for risers, treads and landing plates for interior stairs shall have
a minimum thickness equal to No. 12 Unites States standard gauge iron.
Material used for the construction of exterior steel stairs or fire
escapes shall be at least 1/4 inch in thickness.
D.
Steel joists.
(1)
Form of steel joists. The term "steel joist" shall denote any approved form of open-webbed beam or truss less than 20 inches in depth and produced directly by rolling or pressing or fabricated from rolled or pressed shapes by welding, pressing, riveting or expanding. Limiting provisions in the following paragraphs do not apply to structural steel sections such as hot-rolled solid web T-beams, channels or plate girders which may be used as steel joists, their design, spacing and loading to be governed only by the stresses required in this code, and provided that bridging, as specified in Subsection D(5) hereof, shall be used.
(2)
Use of steel joists. Steel joists may be used elsewhere
than around stairs, shafts and other floor openings as secondary members
for floor fillers in structures 100 feet or less in height.
(3)
Design of steel joists. Steel joists small be designed
using stresses not exceeding those allowed under the Building Code.
Web members shall have the same section throughout.
(4)
Span and spacing of steel joists. The span of joists
having an all steel top chord shall be within 550 times the lateral
radius of gyration of the top chord, but in case the top chord consists
of a flat top section continuous with a center web, the radius or
gyration of the top plate alone shall be taken. The span shall be
within 24 times the depth of the joist. The maximum deflection shall
not be greater than 1/360 of the span for the total load as determined
by test. The maximum spacing of the joists shall be the safe span
of the top slab or flooring over the joist and in no case greater
than 24 inches in floors and 30 inches in roofs, except that steel
joists may be used to support wood or sheet metal roofs only if not
over seven feet apart.
(5)
Loading and bridging of steel joists. Every steel
joist shall be capable of sustaining a concentrated load at any panel
point of at least 800 pounds, except as required elsewhere for concentrated
loads, and shall be securely bridged so that it shall develop, without
failure, 2 1/4 times the total uniformly distributed load for
which it is designed, provided that the bridging is the same as that
to be actually used in the construction, but in no case shall the
bridging be more than six feet apart or six feet from supports. Such
bridging shall securely support the top chord of the joist against
lateral displacement and shall be rigid in character and capable of
transmitting directly at least 500 pounds to the two adjoining joists
at each line of bridging. The steel joists shall be designed to carry
directly the total dead load of partitions where they occur in addition
to all other dead and live loads imposed. During testing, the character
of the bridging shall be such as not to relieve the member of any
fraction of the test load.
(6)
Bearing and anchoring of steel joists. Where steel
joists have a bearing on masonry or concrete, at least four inches
of their length shall be on each such bearing, and the joists shall
be securely anchored to the masonry or concrete. When bearing on steel,
steel joists shall have at least 2 1/2 inches of their length
on each such bearing. The bearing stresses shall not exceed 200 pounds
per square inch on masonry or concrete and 1,000 pounds per square
inch on steel. All joists shall be anchored to supports so as to prevent
dislodgment during erection, and they shall be belted or welded to
all steel supports. Any joists at the end of a panel shall be braced
laterally by anchors or ties at each line of bridging.
(7)
Connections of steel joists. Connections of the various
members of steel joists shall be designed with as little eccentricity
as possible, and all stresses due to eccentricty shall be included
with primary stresses in designing. All such connections shall be
made by leaving a portion of the metal intact or by fusion welding.
All joints and connections shall be capable of resisting at least
three times the designed stress.
(8)
Painting of steel joists. Painting of steel joists shall be in accordance with the requirements of § 86-62C(13), Painting, or the joists shall be dipped once in hot asphalt at the place of manufacture or given two coats of cold asphalt, either by dipping or spraying, at the place of manufacture. When either hot or cold asphalt is used, all abrasions shall be touched up at the job with the same material.
E.
Welding.
(1)
Fusion welding may be substituted for or used in connection
with riveting and bolting, provided that the welding be done in accordance
with the rules promulgated by the Superintendent of Buildings and
approved by the Board of Trustees.
(2)
In the absence of such rules, all welding shall be
done in accordance with the Code of Fusion Welding and Gas Cutting
in Building Construction, 1928 Edition of the American Welding Society,
as amended currently, or its equal.
(3)
Whenever welding is substituted for riveting or bolting,
either wholly or partly, the Superintendent of Buildings may retain
such professional advisors and others qualified to inspect the welding,
as he may deem necessary, to ensure compliance with this section and
the structural safety of all welded portions of a structure. These
services and all expenses attached thereto shall be at the expense
of the owner.
A.
Thickness of wood beams. No wood floor or roof beam
used in any multiple dwelling or in any building hereafter erected
within the fire limits shall be less than three inches thick.
B.
Support of wood structural members.
(1)
The ends of wood beams, joists and rafters resting
on masonry walls shall be cut to a bevel of three inches in their
depth and shall have a bearing of at least four inches on the masonry.
(2)
The ends of wood beams resting on girders shall have
bearings of at least four inches.
(3)
The ends of wood beams framing into girders may be
supported by approved metal stirrups, hangers or bolted hardwood cleats,
provided that all bearings of timber shall be at least four inches
or as may be otherwise designed and shown in detail on the framing
plans and having a bearing within the working stress of the timbers.
(4)
In no case, except in one- and two-family dwellings,
shall either end of a floor or roof beam be supported on stud partitions.
Tail beams over four feet long and trimmer and header beams shall
be hung in approved metal stirrups or hangers and shall be spiked
unless supported on a wall or girder.
(5)
Notching or cutting of wood beams, joists or rafters
is forbidden unless they are suitably reinforced.
(6)
Built-up girders shall be securely bolted together.
Other built-up members shall be securely spiked or bolted together.
Spiked trusses shall be of types which have been tested and approved.
C.
Bridging of wood beams. Wood floor beams and beams
in flat roofs exceeding eight feet in clear span shall be braced with
mitered cross bridging, measuring at least one inch by 2 1/2
inches (actual) and nailed twice at each bearing or, if metal bridging
is used, it must have equivalent effective strength and durability.
The maximum distance between bridging or between bridging and bearing
shall be eight feet.
D.
Anchoring wood beams and girders to masonry. Each tier of beams parallel to masonry and beams and girders bearing on masonry shall provide adequate lateral stability by anchorage as required in § 86-60H, Anchorage of masonry walls.
E.
Fastening of wood beams on girders. The ends of wood beams resting upon girders, walls or bearing partitions required to be anchored in accordance with § 86-60H, Anchorage of masonry walls, except as otherwise provided, shall lap each other at least six inches and be well-bolted or spiked together or shall be butted end to end and fastened by approved metal straps, ties or dogs in the same beams as the wall anchors.
F.
Fastening of wood girders. The ends of wood girders
shall be fastened to each other by approved straps, ties or dogs.
G.
Fire prevention.
(1)
Trimming around flues and fireplaces. Wood beams shall
be trimmed away from flues and chimneys. The header and trimmer beams
shall be at least four inches from the face of chimneys and backs
of fireplaces. In front of a fireplace, an opening shall be trimmed
to support a trimmer arch or approved masonry hearth at least 20 inches
from the face of the breast and at least 12 inches wider on each side
than the fireplace opening.
(2)
Separation of combustible members in masonry walls.
Combustible members entering a masonry wall shall be separated from
each other and from the outside of the wall by at least four inches
of solid masonry.
H.
Wood columns and posts.
(1)
Wood columns and posts shall have level bearings and
shall be supported and shall have properly designed metal bases or
base plates.
(2)
Where timber columns are superimposed, they shall
be squared at the ends perpendicular to their axis and supported on
metal caps with brackets or shall be connected by properly designed
metal caps, pintles and base plates.
I.
Bolting in wood construction. Bolts in wood construction shall be provided with washers and, when carrying tensile stress, they shall be of such proportions that the compression on the wood at the face of the washer will be less than the working stresses prescribed in § 86-53F, Lumber and timbers.
J.
Stud-bearing partitions. Stud-bearing partitions which
rest directly over each other and are not parallel with wood floor
beams shall run down between the wood floor beams and rest on the
top plate of the partition girder or foundation below. For wood frame
dwellings, this may be waived by the Superintendent of Buildings.
Stud-bearing partitions parallel to the floor joists shall be supported
on doubled joists or beams at least as wide as the studs supported.
K.
Fire stops.
(1)
Firestopping of stud-bearing partitions. Exterior
stud walls and stud-bearing partitions shall have the studding filled
in solid between the uprights to the depth of all floor beams with
suitable incombustible materials. In wood frame dwellings, other firestopping
may be used as approved by the Superintendent of Buildings.
(2)
Firestopping of furred spaces. Where walls are furred
off or studded off, the space between the inside of the furring or
studding and the wall shall be fire-stopped from the ceiling to the
underside of the flooring or roof above with incombustible material.
(3)
Firestopping of wainscoting. The surface of the wall
or partition behind wainscoting shall be plastered flush with the
grounds and down to the floor line.
A.
Piers and wharves. Piers and wharves shall be constructed
in accordance with plans prepared by a professional engineer licensed
by the State of New York, said plans to be based on computations using
generally accepted engineering principles and in conformity with applicable
provisions of the Building Code. Live loads must be acceptable to
the Building Department Superintendent. Piers and wharves shall be
constructed on pile or other approved foundations. Piles shall conform
to the specifications for bulkhead piles with regard to type of wood,
treatment, dimensions, taper, straightness and defects.
B.
Bulkheads.
(1)
No plot fronting on navigable water shall be used
for any dwelling or business purpose, nor shall a permit be issued
for the erection, addition or alteration or improvement of any structure
until an approved bulkhead has been erected for the full width of
the plot. All bulkheads erected under this provision shall be maintained
and kept in good state of repair at all times.
[Added 11-9-1970]
(2)
Bulkheads shall be constructed so as to have adequate
structural strength and stability to retain and support the abutting
banks or the material behind some, together with any superimposed
loads, and to resist the action of the tides, boats and the elements.
No portion of any bulkhead shall extend beyond the private property
line. The tops of all bulkheads shall have a minimum elevation of
5.9 feet NAVD (North American Vertical Datum).
[Amended 12-6-1993 by L.L. No. 5-1993; 3-10-2014 by 2-2014]
C.
Minimum bulkhead requirements.
(1)
The minimum bulkhead requirements herein specified
are applicable to conditions where the existing depth of compressible
material (bog) does not exceed eight feet. When the existing depth
of compressible material (bog) exceeds eight feet, the applicant must
submit plans and design computations for bulkhead construction as
prepared by a professional engineer licensed by the State of New York,
said plans and computations to be based on generally accepted engineering
principles and satisfactory to the Village Building Department Superintendent.
(2)
Minimum requirements for the construction of bulkheads
are shown on the drawing annexed hereto, made a part hereof and entitled
"Minimum Bulkhead Requirements -- Village of Freeport," and shall
consist of:
(3)
Where plans accompanying application for permit vary
from the minimum bulkhead requirements, the applicant must submit
design computations prepared by a professional engineer licensed by
the State of New York, said plans and computations based on generally
accepted engineering principles and satisfactory to the Village Building
Department Superintendent.
(4)
Piles shall penetrate into good granular material
a minimum of 1/3 their length. Minimum pile length shall be 20 feet.
(5)
Sheathing boards shall penetrate into good granular
material a minimum of five feet. Minimum length of sheathing boards
shall be 18 feet.
(6)
All timbers, including piles, shall be air-seasoned
and full-cell treated (Bethell process) with creosote-coal tar solution
and shall retain the minimum weights of preservative as recommended
by the American Wood-Preservers Association standards for coastal
waters.
D.
Specifications for wood bulkheads.
(1)
Piles. Piles shall be of sound southern pine or Douglas
fir. Oak piles are not permitted. The minimum tip diameter shall be
six inches, and the minimum butt diameter shall be 12 inches three
feet from the end. Piles shall have reasonably uniform taper and be
so straight that a straight line joining the centers of the butt and
tip shall not be outside the body of the pile. They shall be free
from all defects which may impair their strength and durability.
(2)
Rangers of wales. Rangers of wales shall be Douglas
fir or southern pine with a minimum allowable stress of 1,600 pounds
per square inch. They shall be six inches by eight inches rough with
the eight-inch dimension horizontal. All splices shall be at pile
locations. Wales shall be fastened to piles and sheathing at pile
locations with three-fourths-inch diameter through bolts and OG washers.
(3)
Sheathing boards. Sheathing boards shall be Douglas
fir or southern pine with a minimum allowable stress of 1,600 pounds
per square inch. They shall be three-inch nominal thickness, tongue
and groove and tightly set in place. Each sheathing board shall be
spiked to each wale with two 60D spikes.
(4)
Tieback or anchorage. All piles shall be tied back
by the use of tie-rods and anchorages. Tie-rods shall be of steel,
ASTM A307, with a minimum one-inch diameter. Anchorages shall consist
of a continuous four-by-twelve-inch creosoted plank set horizontally,
with a minimum of four feet of cover and located at least 12 feet
behind the nearside face of the sheathing boards. These planks shall
be of Douglas fir or southern pine with a minimum allowable stress
of 1,600 pounds per square inch. Splices in this plank shall be at
anchor piles only. On the bulkhead side of the aforementioned plank,
anchor piles on twelve-foot spacing shall be installed. Anchor piles
shall be of untreated oak or creosoted pine or fir and be a minimum
of 12 feet long. The tops of all anchor piles shall have at least
three feet of cover above same. The tie-rods shall extend through
the center of both anchor pile and/or plank. At the bulkhead, timber
filler blocks, six inches by eight inches, shall be installed at each
pile location between the pile and the sheathing boards. The tie-rods
shall extend through the sheathing board, filler block and pile at
a point 12 inches below the top wale.
(5)
Backfill behind bulkheads. All existing compressible
material along the line of the bulkhead and for a minimum distance
of one foot behind same shall be excavated and removed. No compressible
material shall be used for backfill within one foot of the inside
face of the bulkhead. Backfill in this area shall be granular material.
(6)
General.
(a)
All work shall conform to the best practices
for the trade involved. All steel rods, bolts, nuts, washers, nails,
spikes, screws, etc., shall conform to ASTM A307, Grade A, and be
hot-dip galvanized after fabrication in conformity with ASTM A153.
OG washers shall be used behind all bolt and rod heads and nuts. All
field cuts, including drilled holes, in timber or piles shall be field-treated
with two applications of hot creosote or hot creosote-coal tar solution.
(b)
The final position of the bulkhead, after back-filling
behind same, shall be straight, vertical and true. The tops of piles
shall also be uniform as to line and grade and set to the required
elevation. The Building Department Superintendent may require, and
the applicant must furnish upon his request, certification regarding
the quality of materials used or to be used for the construction of
the applicant's bulkhead.
(c)
Prior to the delivery of bulkhead materials
to the site, the contractor shall, in the presence of a Building Department
representative, make subsurface soundings at the bulkhead line in
order to determine the elevation of the granular material into which
the piles and sheathing boards must penetrate. The soundings must
be made in a manner satisfactory to the Building Department. In lieu
of the above procedure, the Building Department will accept subsurface
boring data submitted and certified by a professional engineer licensed
in the State of New York.
