The Ontario Building Code | Elements of Structures, Non-structural Components and Equipment

4.1.8.18. Elements of Structures, Non-structural Components and Equipment

(1) Except as provided in Sentences (2) and (8), elements and components of buildings described in Table 4.1.8.18. and their connections to the structure shall be designed to accommodate the building deflections calculated in accordance with Article 4.1.8.13. and the element or component deflections calculated in accordance with Sentence (10), and shall be designed for a lateral force, VP, applied through the centre of mass of the element or component that is equal to:

Vp= 0.3FaSa(0.2) IESpWp

where,

Fa = as defined in Table 4.1.8.4.B.,

Sa(0.2) = spectral response acceleration value at 0.2 s, as defined in Sentence 4.1.8.4.(1),

IE = importance factor for the building, as defined in Article 4.1.8.5.,

Sp = CpArAx/Rp (the maximum value of Spshall be taken as 4.0 and the minimum value of Spshall be taken as 0.7), where,

Cp = element or component factor from Table 4.1.8.18.,

Ar = element or component force amplification factor from Table 4.1.8.18.,

Ax = height factor (1 + 2 hx / hn),

Rp = element or component response modification factor from Table 4.1.8.18., and

Wp = weight of the component or element.

(2) For buildings other than post-disaster buildings, where IEFaSa(0.2) is less than 0.35, the requirements of Sentence (1) need not apply to Categories 6 through 21 of Table 4.1.8.18.

(3) The values of Cp in Sentence (1) shall conform to Table 4.1.8.18.

(4) For the purpose of applying Sentence (1) and Categories 11 and 12 of Table 4.1.8.18., elements or components shall be assumed to be flexible or flexibly connected unless it can be shown that the fundamental period of the element or component and its connection is less than or equal to 0.06 s, in which case the element or component is classified as being rigid or rigidly connected.

(5) The weight of access floors shall include the dead load of the access floor and the weight of permanent equipment, which shall not be taken as less than 25% of the floor live load.

(6) When the mass of a tank plus its contents or the mass of a flexible or flexibly connected piece of machinery, fixture or equipment is greater than 10% of the mass of the supporting floor, the lateral forces shall be determined by rational analysis.

(7) Forces shall be applied in the horizontal direction that results in the most critical loading for design, except for Category 6 of Table 4.1.8.18., where the forces shall be applied up and down vertically.

(8) Connections to the structure of elements and components listed in Table 4.1.8.18. shall be designed to support the component or element for gravity loads, shall conform to the requirements of Sentence (1), and shall also satisfy these additional requirements:

(a) friction due to gravity loads shall not be considered to provide resistance to seismic forces,

(b) Rp for non-ductile connections, such as adhesives or power actuated fasteners, shall be taken as 1.0,

(c) Rp for anchorage using shallow expansion, chemical, epoxy or cast-in place anchors shall be 1.5, where shallow anchors are those with a ratio of embedment length to diameter of less than 8,

(d) power-actuated fasteners and drop-in anchors shall not be used for tension loads,

(e) connections for non-structural elements or components of Category 1, 2 or 3 of Table 4.1.8.18. attached to the side of a building and above the first level above grade shall satisfy the following requirements:

(i) for connections where the body of the connection is ductile, the body shall be designed for values of CP, Ar and Rp given in Table 4.1.8.18., and all of the other parts of the connection, such as anchors, welds, bolts and inserts, shall be capable of developing 2.0 times the nominal yield resistance of the body of the connection, and

(ii) connections where the body of the connection is not ductile shall be designed for values of Cp=2.0, Rp =1.0 and Ar given in Table 4.1.8.18., and

(f) for the purpose of applying Clause (e), a ductile connection is one where the body of the connection is capable of dissipating energy through cyclic inelastic behaviour.

(9) Floors and roofs acting as diaphragms shall satisfy the requirements for diaphragms stated in Article 4.1.8.15.

(10) Lateral deflections of elements or components shall be based on the loads defined in Sentence (1) and lateral deflections obtained from an elastic analysis shall be multiplied by Rp/IE to give realistic values of the anticipated deflections.

(11) The elements or components shall be designed so as not to transfer to the structure any forces unaccounted for in the design, and rigid elements such as walls or panels shall satisfy the requirements of Sentence 4.1.8.3.(6).

(12) Seismic restraint for suspended equipment, pipes, ducts, electrical cable trays, etc. shall be designed to meet the force and displacement requirements of this Article and be constructed in a manner that will not subject hanger rods to bending.

(13) Isolated suspended equipment and components, such as pendant lights, may be designed as a pendulum system provided that adequate chains or cables capable of supporting 2.0 times the weight of the suspended component are provided and the deflection requirements of Sentence (11) are satisfied.

Table 4.1.8.18.
Elements of Structures and Non-structural Components and Equipment

Forming Part of Sentence 4.1.8.18.(1)

Item

Column 1

Category

Column 2

Part or portion of Building

Column 3

Cp

Column 4

Ar

Column 5

Rp

1.

1

All exterior and interior walls except those in Category 2 or 3(1)

1.00

1.00

2.50

2.

2

Cantilever parapet and other cantilever walls except retaining walls(1)

1.00

2.50

2.50

3.

3

Exterior and interior ornamentations and appendages(1)

1.00

2.50

2.50

4.

4

Floors and roofs acting as diaphragms(2)

-

-

-

5.

5

Towers, chimneys, smokestacks and penthouses when connected to or forming part of a building

1.00

2.50

2.50

6.

6

Horizontally cantilevered floors, balconies, beams, etc.

1.00

1.00

2.50

7.

7

Suspended ceilings, light fixtures and other attachments to ceilings with independent vertical support

1.00

1.00

2.50

8.

8

Masonry veneer connections

1.00

1.00

1.50

9.

9

Access floors

1.00

1.00

2.50

10.

10

Masonry or concrete fences more than 1.8 m tall

1.00

1.00

2.50

11.

11

Machinery, fixtures, equipment, ducts and tanks (including contents)

that are rigid and rigidly connected(3)

1.00

1.00

1.25

that are flexible or flexibly connected(3)

1.00

2.50

2.50

12.

12

Machinery, fixtures, equipment, ducts and tanks (including contents) containing toxic or explosive materials, materials having a flash point below 38°C or firefighting fluids

that are rigid and rigidly connected(3)

1.50

1.00

1.25

that are flexible or flexibly connected(3)

1.50

2.50

2.50

13.

13

Flat bottom tanks (including contents) attached directly to a floor at or below grade within a building

0.70

1.00

2.50

14.

14

Flat bottom tanks (including contents) attached directly to a floor at or below grade within a building containing toxic or explosive materials, materials having a flash point below 38°C or firefighting fluids

1.00

1.00

2.50

15.

15

Pipes, ducts, cable trays (including contents)

1.00

1.00

3.00

16.

16

Pipes, ducts (including contents) containing toxic or explosive materials

1.50

1.00

3.00

17.

17

Electrical cable trays, bus ducts, conduits

1.00

2.50

5.00

18.

18

Rigid components with ductile material and connections

1.00

1.00

2.50

19.

19

Rigid components with non-ductile material or connections

1.00

1.00

1.00

20.

20

Flexible components with ductile material and connections

1.00

2.50

2.50

21.

21

Flexible components with non-ductile material or connections

1.00

2.50

1.00

Notes to Table 4.1.8.18.:

(1) See Sentence 4.1.8.18.(8).

(2) See Sentence 4.1.8.18.(9).

(3) See Sentence 4.1.8.18.(4).

Section 4.2. Foundations

4.2.1. General