As It StandsQuality Assurance & Inspection

Dawn Anderson, AIA

(408) 422-6155117*135253*5 Nextel

InstitutionalCommercialResidential

•Architect C-25835• Access Specialist CASp-050• ICC Combination Inspector• Inspector of Record OSHPD A

2059 Camden Ave. Suite 229 • San Jose, CA. • 95124gonedawning@yahoo.com www.asitstands.com

12-

Chapter 13SEISMIC DESIGN REQUIREMENTS FOR NONSTRUCTURAL COMPONENTS

13.1 GENERAL

13.1.1 Scope. This chapter establishes minimum design criteriafor nonstructural components that are permanently attached tostructures and for their supports and attachments.

13.1.2 Seismic Design Category. For the purposes of this chap-ter, nonstructural components shall be assigned to the same seis-mic design category as the structure that they occupy or to whichthey are attached.

13.1.3 Component Importance Factor. All components shallbe assigned a component importance factor as indicated in thissection. Thej:omponent importance factor, /p,_shaj]_be_taken..as1,5 if any of thefoilowing conditions apply:

^~*~_^ 1. The component is required to function forjife-safety pur-

_poses afteran earthquake, including fire protection sprinkler

2. The component contains hazardous materials. N/ftfuyal %xn

3. The component is in or attached to an Occupancy Category7

IV structure and it is needed for continued operation of thefacility or its failure could impair the continued operationof the facility.

All other components shall be assigned a component importancefactor, lp, equal to 1.0. \j.

m

13.1.4 Exemptions. The following [nonstructural componentsare exempt from the requirements of this section:

Architectural components in Seismic Design Category Bother than parapets supported by bearing walls or shear wallsprovided that the component importance factor, /,,, is equalto 1.0.

Mechanical and electrical components in Seismic DesignCategory B.

Mechanical and electrical components in Seismic DesignCategory C provided that the component importance factor,lp, is equal to 1.0.

4. Mechanical and electrical components in Seismic DesignCategories D, E, and F where the component importancefactor, lp, is equal to 1 .0 and either: \3> -a. Flexible connections between the components and asso-

ciated ductwork, piping, and conduit are provided.b. Components are mounted at 4 ft (1.22 m) or less above

a floor level and weigh 400 Ib (1780 N) or less.

5, Mechanical and electrical components in Seismic DesignCategories D, E, and F where the component importancefactor, /,,, is equal to 1.0 and <?<.& f ^ - l - S ^ l J> rt9 .a. Flexible connections between the components and asso-

ciated ductwork, piping, and conduit are provided.b. The components weigh 20 Ib (89 N) or less or, for dis-

tribution systems, weighing 5 Ib/ft (73 N/m) or less.

13.1.5 Applicability of Nonstructural Component Require-ments. Where the weight of a nonstructural component is greaterthan or equal to 25 percent of the effective seismic weight, W,defined in Section 12.7.2, the component shall be classified as anonbuilding structure and shall be designed in accordance withSection 15.3.2. tl

Nonbuilding structures (including storage racks and tanks) thatare supported by other structures shall be designed in accordancewith Chapter 15. Where Section 15.3 requires that seismic forcesbe determined in accordance with Chapter 13 and values for RP

are not provided in Table 13.5-1 or 13.6-1, Rp shall be taken asequal to the value of R listed in Section 15. The value of ap shallbe determined in accordance with footnote a of Table 13.5-1 or13.6-1.

13.1.6 Reference Documents. Where a reference documentprovides a basis for the earthquake-resistant design of a particulartype of system or component, that document is permitted to beused, subject to the approval of the authority having jurisdictionand the following conditions:

a. The design earthquake forces shall not be less than those de-termined in accordance with Section 13.3.1.

b. Each component's seismic interactions with all other con-nected components and with the supporting structure shall beaccounted for in the design. The component shall accommo-date drifts, deflections, and relative displacements determinedin accordance with the applicable seismic requirements of thisstandard.

13.1.7 Reference Documents Using Allowable Stress Design.Where a reference document provides a basis for the earthquake-resistant design of a particular type of system or component, andthe same reference document defines acceptance criteria in termsof allowable stresses rather than strengths, that reference docu-ment is permitted to be used. The allowable stress load combina-tion shall consider dead, live, operating, and earthquake loads inaddition to those in the reference document. The earthquake loadsdetermined in accordance with Section 13.3.1 shall be multipliedby a factor of 0.7. The allowable stress design load combina-tions of Section 2.4 need not be used. The component or systemshall also accommodate the relative displacements specified inSection 13.3.2.

13.2 GENERAL DESIGN REQUIREMENTS

13.2.1 Applicable Requirements for Architectural, Mechani-cal, and Electrical Components, Supports, and Attachments.Architectural, mechanical, and electrical components, supports,and attachments shall comply with the sections referenced inTable 13.2-1. These requirements shall be satisfied by one of thefollowing methods:

1. Project-specific design and documentation prepared andsubmitted by a registered design professional.

Minimum Design Loads for Buildings and Other Structures V 1 * A -111 I \o*} 143

TABLE 13.2-1 APPLICABLE REQUIREMENTS FOR ARCHITECTURAL, MECHANICAL, AND ELECTRICAL COMPONENTS:SUPPORTS AND ATTACHMENTS

Nonstructural Element(i.e., Component. Support,Attachment)

Architectural Componentsand Supports andAttachments forArchitectural Components

Mechanical and ElectricalComponents with lp > 1

Supports and Attachmentsfor Mechanical andElectrical Components

General DesignRequirements Section 13.2

X

X

X

Force and DisplacementRequirements Section 13.3

X

X

X

Attachment RequirementsSection 13.4

X

X

X

Architectural ComponentRequirements Section 13,5

X

Mechanical and ElectricalComponent Requirements

Section 13.6

X

X

2. Submitta! of the manufacturer's certification that the com-ponent is seismically qualified by

a. Analysis.b. Testing in accordance with the alternative set forth in

Section 13.2.5.c. Experience data in accordance with the alternative set

forth in Section 13.2.6.

13.2.2 Special Certification Requirements for DesignatedSeismic Systems. Certitications shall be provided for designatedseismic systems assigned to Seismic Design Categories C throughF as follows:

a. Active mechanical and electrical equipment that must remainoperable following the design earthquake shall be certified bythe supplier as operable based on approved shake table testingin accordance with Section 13.2.5 or experience data in ac-cordance with Section 13.2.6. Evidence demonstrating com-pliance of this requirement shall be submitted to the authorityhaving jurisdiction after review and approval by the registereddesign professional.

b. Components with hazardous contents shall be certified bythe*supplier as maintaining containment following the designearthquake by (1) analysis, (2) approved shake table testingin accordance with Section 13.2.5, or (3) experience data inaccordance with Section 13.2.6. Evidence demonstrating com-pliance of this requirement shall be submitted to the authorityhaving jurisdiction after review and approval by the registereddesign professional.

13.2.3 Consequential Damage. The functional and physical in-terrelationship of components, their supports, and their effect oneach other shall be considered so that the failure of an essential ornonessential architectural, mechanical, or electrical componentshall not cause the failure of an essential architectural, mechani-cal, or electrical component.

13.2.4 Flexibility. The design and evaluation of components,their supports, and their attachments shall consider their flexi-bility as well as their strength.

13.2.5 Testing Alternative for Seismic Capacity Determina-tion. As an alternative to the analytical requirements of Sec-tions 13.2 through 13.6, testing shall be deemed as an acceptablemethod to determine the seismic capacity of components andtheir supports and attachments. Seismic qualification by testingbased upon a nationally recognized testing standard procedure,such as ICC-ES AC 156, acceptable to the authority having ju-risdiction shall be deemed to satisfy the design and evaluationrequirements provided that the substantiated seismic capacitiesequal or exceed the seismic demands determined in accordancewith Sections 13.3.1 and 13.3.2.

13.2.6 Experience Data Alternative for Seismic CapacityDetermination. As an alternative to the analytical requirementsof Sections 13.2 through 13.6, use of experience data shall bedeemed as an acceptable method to determine the seismic capac-ity of components and their supports and attachments. Seismicquali fication by experience data based upon nationally recognizedprocedures acceptable to the authority having jurisdiction shallbe deemed to satisfy the design and evaluation requirements pro-vided that the substantiated seismic capacities equal or exceed theseismic demands determined in accordance with Sections 13.3.1and 13.3.2.

13.2.7 Construction Documents. Where design of nonstruc-tural components or their supports and attachments is requiredby Table 13.2-1, such design shall be shown in constructiondocuments prepared by a registered design professional for useby the owner, building officials, contractors, and inspectors. Suchdocuments shall include a quality assurance plan if required byAppendix 11A.

13.3 SEISMIC DEMANDS ON NONSTRUCTURALCOMPONENTS

13.3.1 Seismic Design Force. The horizontal seismic designforce (/•',,) shall be applied at the component's center of grav-ity and distributed relative to the component's mass distributionand shall be determined in accordance with Eq. 13.3-1:

_

Fp is not required to be taken as greater than

and Fp shall not be taken as less than

where

(13.3-1)

(13.3-2)

(13.3-3)

Fp = seismic design forceSDS = spectral acceleration, short period, as determined from

Section 11.4.4a,, — component amplification factor that varies from 1.00

to 2.50 (select appropriate value from Table 13.5-1 or13.6-1)

IP = component importance factor that varies from 1.00 to 1.50(see Section 13.1.3)

Wp — component operating weightRp =. component response modification factor that varies from

1.00 to 12 (select appropriate value from Table 13.5-1 or13.6-1)

144 ASCE 7-05

z — height in structure of point of attachment of componentwith respect to the base. For items at or below the base, zshall be taken as 0. The value o f z / h need not exceed 1.0

h = average roof height of structure with respect to the base

The force (Fp) shall be applied independently in at least two or-thogonal hori/ontal directions in combination with service loadsassociated with the component, as appropriate. For verticallycantilevered systems, however, the force Fr, shall be assumed toact in any horizontal direction. In addition, the component shallbe designed for a concurrent vertical force ±0.25oi-W;j, The re-dundancy factor, p, is permitted to be taken equal to 1 and theoverstrength factor, £2o. does not apply.

EXCEPTION: The concurrent vertical seismic force need not be con-sidered for lay-in access floor panels and lay-in ceiling panels.

Where nonseismic loads on nonstructural components exceed Ffl,such loads shall govern the strength design, but the detailing re-quirements and limitations prescribed in this chapter shall apply.

In lieu of the forces determined in accordance with Eq. 13.3-1,accelerations at any level are permitted to be determined by themodal analysis procedures of Section 12.9 with R = I.(). Seismicforces shall be in accordance with Eq. 13.3-4:

*(13.3-4)

Where a,- is the acceleration at level < obtained from the modalanalysis and where At is the torsionai amplification factordetermined by Eq.12.8-14. Upper and lower limits of F,, deter-mined by Eqs. 13.3-2 and 13.3-3 shall apply.

13.3.2 Seismic Relative Displacements. The effects of seismicrelative displacements shall be considered in combination withdisplacements caused by other loads as appropriate. Seismic rel-ative displacements (Dp) shall be determined in accordance withthe equations set forth in Sections 13.3.2.1 and 13.3.2.2.

13.3.2.1 Displacements within Structures. For two connection /points on the same Structure A or the same structural system, oneat a height hx and the other at a height hy, Dt, shall be determined

Dp =*,*-&„ A (13.3-5)

Alternatively, Dt, is permitted to be determined using modal pro-cedures described in Section 12.9, using the difference in storydeflections calculated for each mode and then combined usingappropriate modal combination procedures. Dp is not required tobe taken as greater than

(hx -/iv) Afl.4(13.3-6)

13.3.2.2 Displacements between Structures. For two connec-tion points on separate Structures A and B or separate structuralsystems, one at a height hx and the other at a height hy, Dp shallbe determined as

Dp = 1

Df is not required to be taken as greater than

(13.3-7)

(13.3-8)

(5vg =

where

Df, = relative seismic displacement that the component must bedesigned to accommodate

<§r/j = deflection at building Level x of Structure A, determinedby an elastic analysis as defined in Section 12.8.6

&yA — deflection at building Level y of Structure A, determinedby an elastic analysis as defined in Section 12.8.6deflection at building Level y of Structure B, determinedby an elastic analysis as defined in Section 12.8.6height of Levelattachedheight of Levelattachedallowable story drift for Structure A as defined inTable 12.12-1allowable story drift for Structure B as defined inTable 12.12-1story height used in the definition of the allowable driftA0 in Table 12. 12-1. Note that A(1//iJV = the drift index.

The effects of seismic relative displacements shall be consid-ered in combination with displacements caused by other loads asappropriate.

Afl/(

Aag

hsj,

x to which upper connection point is

y to which lower connection point is

13.4 NONSTRUCTURAL COMPONENTANCHORAGE

Components and their supports shall be attached (or anchored) tothe structure in accordance with the requirements of this sectionand the attachment shall satisfy the requirements for the parent-material as set forth elsewhere in this standard.

Component attachments shall be bolted, welded, or otherwisepositively fastened without consideration of frictional resistanceproduced by the effects of gravity. A continuous load path of suf-ficient strength and stiffness between the component and the sup-porting structure shall be provided. Local elements of the structureincluding connections shall be designed and constructed for thecomponent forces where they control the design of the elementsor their connections. The component forces shall be those de-termined in Section 13.3.1, except that modifications to Fp andRp due to anchorage conditions need not be considered. The de-sign documents shall include sufficient information relating tothe attachments to verify compliance with the requirements ofthis section.

•^**^~~-—^__—~-13.4.1 Design Forces. The force in the attachment shall be de-termined based on the prescribed forces and displacements for thecomponent determined specified in Sections 13.3.1 and 13.3.2.

13.4.2 Anchors in Concrete or Masonry. Anchors embeddedin concrete or masonry shall be proportioned to carry the least ofthe following:

a. 1.3 times the force in the component and its supports due tothe prescribed forces.

b. The maximum force that can be transferred to the anchor bythe component and its supports.

The value of Rp used in Section 13.3.1 to determine the forces inthe connected part shall not exceed 1.5 unless

a. The component anchorage is designed to be governed by thestrength of a ductile steel element.

b. The design of post-installed anchors in concrete used for thecomponent anchorage is prequalified for seismic applicationsin accordance with ACI 355.2.

c. The anchor is designed in accordance with Section 14.2.2.14.

Minimum Design Loads for Buildings and Other Structures 145

13.4.3 Installation Conditions. Determination of forces inattachments shall take into account the expected conditions ofinstallation including eccentricities and prying effects.

13.4.4 Multiple Attachments. Determination of force distribu-tion of multiple attachments at one location shall lake into accountthe stiffness and ductility of the component, component supports.attachments, and structure and the ability to redistribute loads toother attachments in the group. Designs of anchorage in concretein accordance with Appendix D of ACI 318 shall be consideredto satisfy this requirement.

13.4.5 Power Actuated Fasteners. Power actuated fastenersshall not be used for tension load applications in Seismic DesignCategories D, E, and F unless approved for such loading.

13.4.6 Friction Clips. Friction clips shall not be used for anchor-'age attachment.

l3j~ARCHificfuRAL COMPONENTS

13.5.1 General. Architectural components, and their supportsand attachments, shall satisfy the requirements of this section.Appropriate coefficients shall be selected from Table 13.5-1.

EXCEPTIONS: Components supported by chains or otherwise sus-pended from the structure are not required to satisfy the seismic forceand relative displacement requirements provided they meet all of the fol-lowing criteria:

1. The design load for such items shall be equal to 1.4 times the oper-ating weight acting down with a simultaneous horizontal load equalto 1.4 times the operating weight. The horizontal load shall be ap-plied in the direction that results in the most critical loading lordesign.

2. Seismic interaction effects shall be considered in accordance withSection 13.2.3.

3. The connection lo the structure shall allow a 360" range of motionin the horizontal plane.

13.5.2 Forces and Displacements. All architectural compo-nents, and their supports and attachments, shall be designed forthe seismic forces defined in Section 13.3.1,

Architectural components that could pose a life-safety haz-ard shall be designed to accommodate the seismic relative dis-placement requirements of Section 13.3.2. Architectural compo-nents shall be designed considering vertical deflection due to jointrotation of cantilever structural members.

* 13.5.3 Exterior Nonstructural Wall Elements and Connec-tions. Exterior nonstructural wall panels or elements that are at-tached to or enclose the structure shall be designed to accommo-date the seismic relative displacements defined in Section 13.3.2and movements due to temperature changes. Such elements shallbe supported by means of positive and direct structural supportsor by mechanical connections and fasteners in accordance with

\ the following requirements:'-1 •'

U

TABLE 13.5-1 COEFFICIENTS FOR ARCHITECTURAL COMPONENTArchitectural Component or Element

Interior Nonstructural Wails and Partitions'"Plain (unreinforced) masonry wallsAll other walls and partitions

Cantilever Elements (Unbraced or braced to structural frame below its center of mass)Parapets and cantilever interior nonstructural wallsChimneys and stacks where laterally braced or supported by the structural frame

Cantilever Elements (Braced to structural frame above its center of mass)ParapetsChimneys and StacksExterior Nonstructura! Walls'

Exterior Nonstructural Wall Elements and Connections*Wall ElementBody of wall panel connectionsFasteners of the connecting system

VeneerLimited deformability elements and attachmentsLow deformability elements and attachments

Penthouses (except where framed by an extension of the building frame)

CeilingsAll

CabinetsStorage cabinets and laboratory equipment

Access FloorsSpecial access floors (designed in accordance with Section 13.5.7.2)All other

Appendages and Ornamentations

Signs and Billboards

Other Rigid ComponentsHigh deformability elements and attachmentsLimited deformability elements and attachmentsLow deformability materials and attachments

Other Flexible ComponentsHigh deformability elements and attachmentsLimited deformability elements and attachmentsLow deformabiiity materials and attachments

»P'

1.01.0

2.52.5

1,01.01.0*

1.01.01.25

1.01.0

2.5

1.0

1.0

1.01.0

2.52.5

1.01.01.0

2.52.52.5

3?

1.52.5

2.52.5

2.52.52.5

2.52.51.0

2.51.5

3.5

2.5

2.5

2.51.5

2.5

2.5

3.52.51.5

352.51.5

"A lower value for ap shall not be used unless justified by detailed dynamic analysis. The value for af shall not beless than 1.00. The value of ap = 1 is for rigid components and rigidly attached components. The value of ap = 2.5 isfor flexible components and flexibly attached components. See Section 11.2 for definitions of rigid and flexible.

''Where flexible diaphragms provide lateral support for concrete or masonry walls and partitions, the design forces foranchorage to the diaphragm shall be as specified in Section 12.11.2.

146 ASCE 7-05

a. Connections and panel joints shall allow for the story driftcaused by relative seismic displacements (Dp) determined inSection 13,3,2, or 0,5 in. (13 mm), whichever is greatest,

b. Connections to permit movement in the plane of the panel forstory drift shall be sliding connections using slotted or oversizeholes, connections thai permit movement by bending of steei,or other connections that provide equivalent sliding or ductilecapacity.

c. The connecting member itself shall have sufficient ductilityand rotation capacity to preclude fracture of the concrete orbrittle failures at or near welds.

d. All fasteners in the connecting system such as bolts, inserts,welds, and dowels and the body of the connectors shall bedesigned for the force (Fp) determined by Section 13.3.1 withvalues of Rp and ap taken from Table 13.5-1 applied at thecenter of mass of the panel.

e. Where anchorage is achieved using flat straps embedded inconcrete or masonry, such straps shall be attached to or hookedaround reinforcing steel or otherwise terminated so as to effec-tively transfer forces to the reinforcing steel or to assure thatpullout of anchorage is not the initial failure mechanism.

13.5.4 Glass. Glass in glazed curtain walls and storefronts shallbe designed and installed in accordance with Section 13.5.9.

13.5.5 Out-of-Plane Bending. Transverse or out-of-plane bend-ing or deformation of a component or system that is subjectedto forces as determined in Section 13.5.2 shall not exceed thedeflection capability of the component or system,

13.5.6 Suspended Ceilings.

13.5.6.1 Seismic Forces. The weight of the ceiling, Wp, shallinclude the ceiling grid and panels; light fixtures if attached to,clipped to, or laterally supported by the ceiling grid; and othercomponents that are laterally supported by the ceiling. Wp shallbe taken as not less than 4 psf (19 N/m2).

The seismic force, Fp, shall be transmitted through the ceilingattachments to the building structural elements or the ceiling-structure boundary.

13.5.6.2 Industry Standard Construction. Unless designed inaccordance with Section 13.5.6.3, suspended ceilings shall bedesigned and constructed in accordance with this section.

13.5.6.2.1 Seismic Design Category C. Suspended ceilingsin structures assigned to Seismic Design Category C shall bedesigned and installed in accordance with ASTM C635, ASTMC636, and the CISCA for Seismic Zones 0-2, except that seismicforces shall be determined in accordance with Sections 13.3.1 and13.5.6.1.

13.5.6.2.2 Seismic Design Categories I) through F, Sus-pended ceilings in Seismic Design Categories D, E, and F shall bedesigned and installed in accordance with ASTM C635, ASTM

• C636, and the CISCA for Seismic Zones 3-4 as modified by thefollowing:

a. A heavy duty T-bar grid system shall be used.

b. The width of the perimeter supporting closure angle shall benot less than 2.0 in. (50 mm). In each orthogonal horizontaldirection, one end of the ceiling grid shall be attached to theclosure angle. The other end in each horizontal direction shallhave a 0.75 in. (19 mm) clearance from the wall and shall restupon and be free to slide on a closure angle.

For ceiling areas exceeding 1,000 ft2 (92.9 nr), horizontal re-straint of the ceiling to the structural system shall be provided.

The tributary areas of the horizontal restraints shall be approx-imately equal.

EXCEPTION: Rigid braces are permitted to be used instead of di-agonal splay wires. Braces and attachments to the structural systemabove shall be adequate to limit relative lateral deflections at point ofattachment of ceiling grid to less than 0,25 in. (6 mm) for the loadsprescribed in Section 13.3.1.

d. For ceiling areas exceeding 2,500 ft2 (232 m2), a seismic sepa-ration joint or full height partition that breaks the ceiling up intoareas not exceeding 2,500 ft2 shall be provided unless struc-tural analyses are performed of the ceiling bracing system forthe prescribed seismic forces that demonstrate ceiling systempenetrations and closure angles provide sufficient clearanceto accommodate the anticipated lateral displacement. Each

\ area shall be provided with closure angles in accordance with"Item/I and horizontal restraints or bracing in accordance with

item fh~- c.

e. Except where rigid braces are used to limit lateral deflec-tions, sprinkler heads and other penetrations shall have a 2 in.(50 mm) oversize ring, sleeve, or adapter through the ceilingtile to allow for free movement of at least 1 in. (25 mm) inall horizontal directions. Alternatively, a swing joint that canaccommodate 1 in. (25 mm) of ceiling movement in all hori-zontal directions is permitted to be provided at the top of thesprinkler head extension.

f. Changes in ceiling plan elevation shall be provided with posi-tive bracing, f vu* i v\-f e*~r4

g. Cable trays and electrical conduits shall be supported indepen-dently of the ceiling. efesji n-ee*^ a

h. Suspended ceiling shall b;e .subject to the special inspection(. requirements of Section 11 A. 1.3.9 of this standard. j-~« -

Minimum Design Loads for Buildings and Other Structures

13.5.6.3 Integral Construction. As an alternate to providinglarge clearances around sprinkler system penetrations throughceiling systems, the sprinkler system and ceiling grid are per-mitted to be designed and tied together as an integral unit. Sucha design shall consider the mass and flexibility of all elementsinvolved, including the ceiling system, sprinkler system, lightfixtures, and mechanical (HVAC) appurtenances. Such designshall be performed by a registered design professional.

13.5.7 Access Floors.

13.5.7.1 General. The weight of the access floor, Wp, shall in-clude the weight of the floor system, 100 percent of the weight ofall equipment fastened to the floor, and 25 percent of the weightof all equipment supported by, but not fastened to the floor. Theseismic force, Fp, shall be transmitted from the lop surface of theaccess floor to the supporting structure.

Overturning effects of equipment fastened to the access floorpanels also shall be considered- The ability of "slip on" heads forpedestals shall be evaluated for suitability to transfer overturningeffects of equipment.

Where checking individual pedestals for overturning effects,the maximum concurrent axial load shall not exceed the portionof Wp assigned to the pedestal under consideration.

13.5.7.2 Special Access Floors. Access floors shall be consid-ered to be "special access floors" if they are designed to complywith the following considerations:

1. Connections transmitting seismic loads consist of me-chanical fasteners, anchors satisfying the requirements ofAppendix D of ACI 318, welding, or bearing. Design loadcapacities comply with recognized design codes and/orcertified test results.

147

2. Seismic loads are not transmitted by friction, power actuatedfasteners, adhesives, or by friction produced solely by theeffects of gravity.

3. The design analysis of the bracing system includes thedestabilizing effects of individual members buckling incompression.

4. Bracing and pedestals are of structural or mechanical shapesproduced to ASTM specifications that specify minimummechanical properties. Electrical tubing shall not be used.

5. Floor stringers that are designed to carry axial seismic-loads and that are mechanically fastened to the supportingpedestals are used.

13.5.8.1 General. Partitions that are tied to the ceiling and allpartitions greater than 6 ft (1.8 m) in height shall be laterallybraced to the building structure. Such bracing shall be independentof any ceiling splay bracing. Bracing shall be spaced to limithorizontal deflection at the partition head to be compatible withceiling deflection requirements as determined in Section 13.5.6for suspended ceilings and elsewhere in this section for othersystems.

EXCEPTION: Partitions (hat meet all of the following conditions:1. The partition height does not exceed 9 ft (2,740 mm).

2. The linear weight of the partition does not exceed the product of 10 Ib(0.479 kN) times the height (ft) of the partition.

3. The partition horizontal seismic load does not exceed 5 psf. '

13.5.8.2 Glass. Glass in glazed partitions shall be designed andinstalled in accordance with Section 13.5.9.

13.5.9 Glass in Glazed Curtain Walls, Glazed Storefronts, andGlazed Partitions.

13.5.9.1 General. Glass in glazed curtain walls, glazed store-fronts, and glazed partitions shall meet the relative displacementrequirement of Eq. 13.5-1:

A/«//0«, > 1.25/Z)P (13.5-1)

or 0.5 in. (13 mm), whichever is greater where:

where

= the relative seismic displacement (drift) at which glassfallout from the curtain wall, storefront wall, or partitionoccurs (Section 13.5.9.2)

Dp = the relative seismic displacement that the componentmust be designed to accommodate (Eq, 13.3-2). Dp

shall be applied over the height of the glass componentunder consideration

/ = the occupancy importance factor (Table 11.5-1)

EXCEPTIONS:1. Glass with sufficient clearances from its frame such that physical con-

tact between the glass and frame will not occur at the design drift, asdemonstrated by Eq. 13.5-2, need not comply with this requirement:

where

D,irar > 1.25Dp (13.5-2)

cteur — relative horizontal (drift) displacement, measured over theheight of the glass panel under consideration, which causesinitial glass-to-frame contact. For rectangular glass panelswithin a rectangular wall frame

148

hp = the height of the rectangular glass panelbt, — the width of the rectangular glass panelC| = the clearance (gap) between the vertical glass edges and the

framecj = the clearance (gap) between the horizontal glass edges and

the frame

2. Fully tempered monolithic glass in Occupancy Categories 1,11, and (IIlocated no more than 10 ft (3 m) above a walking surface need notcomply with this requirement.

3. Annealed or heat-strengthened laminated glass in single thickness withinterJayer no less than 0.030 in. (0.76 mm) that is captured mechanicallyin a wall system gla/ing pocket, and whose perimeter is secured to theframe by a wet glazed gunable curing clastomeric sealant perimeierhead of 0.5 in. (13 mm) minimum glass contact width, or other approvedanchorage system need not comply with this requirement.

13.5.9.2 Seismic Drift Limits for Glass Components. A/fl//OH/,the drift causing glass fallout from the curtain wall, storefront, orpartition shall be determined in accordance with AAMA 501.6,or by engineering analysis.

MECHANICAL AND ELECTRICALCOMPONENTS

13.6

13.6.1 General. Mechanical and electrical components and theirsupports shall satisfy the requirements of this section. The attach-ment of mechanical and electrical components and their supportsto the structure shall meet the requirements of Section 13.4. Ap-propriate coefficients shall be selected from Table 13.6-1.

EXCEPTIONS: Light fixtures. lighted signs, and ceiling fans not con-nected to ducts or piping, which are supported by chains or otherwisesuspended from the structure, are not required to satisfy the seismic forceand relative displacement requirements provided they meet all of thefollowing criteria:1. The design load for such items shall be equal to 1.4 times the operat-

ing weight acting down with a simultaneous horizontal load equal to1.4 times the operating weight. The horizontal load shall be applied inthe direction that results in (he most critical loading for design.

2. Seismic interaction effects shall be considered in accordance withSection 13.2.3.

3. The connection to the structure shall allow s. 360" range of motion inthe horizontal plane-

Where design of mechanical arid electrical components for seis-mic effects is required, consideration shall be given to the dynamiceffects of the components, their contents, and where appropriate,their supports. In such cases, the interaction between the compo-nents and the supporting structures, including other mechanicaland electrical components, shall also be considered.

f- -? Set IfeA fir ffrvl txMlticM -to c*d613.6.2 Component Period. The fundamental period of the me-chanical and electrical component (and its attachment to the build-ing), Tp, shall be determined by the following equation providedthat the component and attachment can be reasonably representedanalytically by a simple spring and mass single degree-of-freedomsystem:

(13.6-1)

where

Tt, = component fundamental periodWp = component operating weight

g = gravitational accelerationKp = stiffness of resilient support system of the component and

attachment, determined in terms of load per unit deflectionat the center of gravity of the component

ASCE 7-05

TABLE 13.6-1 SEISMIC COEFFICIENTS FOR MECHANICAL AND ELECTRICAL COMPONENTSMECHANICAL AND ELECTRICAL COMPONENTS

Air-side HVAC. fans, air handlers, air conditioning units, cabinet heaters, air distribution boxes, and other mechanical componentsconstructed of sheet metal framing.

Wet-side HVAC, boilers, furnaces, atmospheric tanks and bins, chillers, water heaters, heal exchangers, evaporators, air separators,manufacturing or process equipment, and othci mechanical components constructed of high-deformability materials.

Engines, turbines, pumps, compressors, and pressure vessels not supported on skirts and not within the scope of Chapter 15.

Skirt- supported pressure vessels not within the scope of Chapter 15.

Elevator and escalator components.

Generators, batteries, inverters, motors, transformers, and other electrical components constructed of high deformability materials.

Motor control centers, panel boards, switch gear, instrumentation cabinets, and other components constructed of sheet metal framing.

Communication equipment, computers, instrumentation, and controls.

Roof-mounted chimneys, stack*,, cooling ami electrical towers laterally braced below their center of mass.

Roof-mounted chimneys, slacks, cooling and electrical towers laterally braced above their center of mass.

Lighting fixtures.

Other mechanical or electrical components.

VIBRATION ISOLATED COMPONENTS AND SYSTEMS"

Components and systems isolated using neoprene elements and neoprene isolated floors with built-in or separate elastorneric snubbingdevices or resilient perimeter stops.

Spring isolated components and systems and vibration isolated floors closely restrained using built-in or separate elastorneric snubbingdevices or resilient perimeter stops.

Internally isolated components and systems.

Suspended vibration isolated equipment including in-line duct devices and suspended internally isolated components.

DISTRIBUTION SYSTEMS

Piping in accordance with ASME B3 1 , including in-line components with joints made by welding or brazing.

Piping in accordance with ASME B3 1 , including in-line components, constructed of high or limited deformability materials, with jointsmade by threading, bonding, compression couplings, or grooved couplings.

Piping and tubing not in accordance with ASME B31, including in-line components, constructed of high-deformability materials, withjoints made by welding or brazing.

Piping and tubing not in accordance with ASME B3 1 , including in-line components, constructed of high- or limited-dcformabilitymaterials, with joints made by threading, bonding, compression couplings, or grooved couplings.

Piping and tubing constructed of low-deformability materials, such as casl iron, glass, and nonductile plastics.

Ductwork, including in-line components, constructed of high-deformability materials, with joints made by welding or brazing.Ductwork, including in-line components, constructed of high- or limiied-deformability materials with joints made by means other thanwelding or brazing.

Ductwork, including in-line components, constructed of low-deformability materials, such as cast iron, glass, and nonductile plastics.

Electrical conduit, bus ducts, rigidly mounted cable trays, and plumbing.

Manufacturing or process conveyors (nonpersonnel).

Suspended cable trays.

a/

2.5

1.0

1.0

2.51.01.0

2.51.02.5i . O

1.01.0

2.5

2.5

2.52.5

2.52.5

2.5

2.5

2.5

2.52.5

2.51.02.52.5

V6.0

2.5

2.52.5

2.52.5

6.0

2.53.02,51.5

1.5

2.5

2.0

2.02.5

12.0

6.0

9.0

4.5

10

9.06.0

3.02.5

3.06.0

"A lower value for n,, is permitted where justified by detailed dynamic analyses. The value for a/, shall not be less than 1.0. The value of a,, equal to 1.0 is forrigid components and rigidly attached components. The value of at, equal to 2.5 is for flexible components and flexibly attached components.

''Components mounted on vibration isolators shall have a bumper restraint or snubber in each horizontal direction. The design force shall be taken as 2Fp if thenominal clearance (air gap) between the equipment support frame and restraint is greater than 0.25 in. If the nominal clearance specified on the constructiondocuments is not greater than 0.25 in., the design force is permitted to be taken as Fp.

Alternatively, the fundamental period of the component in s (Tp)is permitted to be determined from experimental test data or by aproperly substantiated analysis.

13.6.3 Mechanical Components. HVAC ductwork shall meetthe requirements of Section 13:6.7. Piping systems shall meet therequirements of Section 13.6,8. Boilers and vessels shall meet therequirements of Section 13.6.9. Elevators shall meet the require-ments of Section 13.6.10. All other mechanical components shallmeet the requirements of Section 13.6.11. Mechanical compo-nents with Ip greater than 1.0 shall be designed for the seismicforces and relative displacements defined in Sections 13.3.1 and \13.3.2 and shall satisfy the following additional requirements:

1. Provision shall be made to eliminate seismic impact forcomponents vulnerable to impact, for components con-structed of nonductile materials, and in cases where materialductility will be reduced due to service conditions (e.g., lowtemperature applications).

2. Thepossibilityofloadsimposedoncomponentsbyattached iutility or service lines, due to differential movement of sup-port points on separate structures, shall be evaluated.

Minimum Design Loads for Buildings and Other Structures JAtfOuAik wir£ !i& Safety /

3. Where piping or HVAC ductwork components are attachedto structures that could displace relative to one another andfor isolated structures where such components cross theisolation interface, the components shall be designed toaccommodate the seismic relative displacements defined inSection 13.3.2.

13.6.4 Electrical Components. Electrical components with Ip \greater than 1.0 shall be designed for the seismic forces and rela- {live displacements defined in Sections 13.3.1 and 13.3.2 and shall ]satisfy the following additional requirements:

1. Provision shall be made to eliminate seismic impact betweencomponents.

2. Loads imposed on the components by attached utility orservice lines that are attached to separate structures shall beevaluated.

3. Batteriesjm racks shalljiave wraparound restraints to en^sure that thebatteries will not falHrgrn the racL_Spacersshall be used between restraints and cells to prevent damage{(Teases. Racks shall be evaluated for sufficient lateral loadcapacity.

r 149

4. Internal coils of dry type transformers shall be positivelyattached to their supporting substructure within the trans-former enclosure.

5. Electrical control panels, computer equipment, and otheritems with slide-out coranisrh to hold the components in place.

6. Electrical cabinet design shall comply with the applica-ble National Electrical Manufacturers Association (NEMA)standards. Q^uJ:sJn_jlie^.l2w^r^hearjpanel^ that have not

_been_rnadeby_thernanufacturcr.and.reducesignificantly thejjti£a£th_pf the cabinet shall be specifically evaluated.

7. The attachments for additional external items weighingmore than 100 Ib (445 N) shall be specifically evaluatedif not provided by the manufacturer.

8. Where conduit, cable trays, or similar electrical distributioncomponents are attached to structures that could displacerelative to one another and for isolated structures wheresuch components cross the isolation interface, the compo-nents shall be designed to accommodate the seismic relativedisplacements defined in Section 13.3.2.

13.6.5 Component Supports.~MecTianTcal and electrical com-ponent supports (including those with Ip = 1.0) and the meansby which they are attached to the component shall be designedfor the forces and displacements determined in Sections 13.3.1and 13.3.2. Such supports include structural members, braces,frames, skins, legs, saddles, pedestals, cables, guys, stays, snub-bers, and (ethers, as well as elements forged or cast as a part ofthe mechanical or electrical component.

13.6.5.1 Design Basis. If standard supports, forexample, ASMEB31, NFPA 13, or MSS SP-58, or proprietary supports are used,they shall be designed by either load rating (i.e., testing) or for thecalculated seismic forces. In addition, the stiffness of the support,where appropriate, shall be designed such that the seismic loadpath for the component performs its intended function.

13.6.5.2 Design for Relative Displacement. Component sup-ports shall be designed to accommodate the seismic relative dis-placements between points of support determined in accordancewith Section 13.3.2.

13.6.5.3 Support Attachment to Component. The means bywhich supports are attached to the component, except where in-tegral (i.e., cast or forged), shall be designed to accommodateboth the forces and displacements determined in accordance withSections 13.3.1 and 13.3.2. If the value of 1P = 1.5 for the com-ponent, the local region of the support attachment point to thecomponent shall be evaluated for the effect of the load transfer onthe component wall.

13.6.5.4 Material Detailing Requirements. The materialscomprising supports and the means of attachment to the compo-nent shall be constructed of materials suitable for the application,including the effects of service conditions, for example, low tem-perature applications. Materials shall be in conformance with anationally recognized standard.

13.6.5.5 Additional Requirements. The following additionalrequirements shall apply to mechanical and electrical componentsupports:

1. Seismic supports shall be constructed so that support en-gagement is maintained.

2. Oversized plate washers or otherreinforcement shall be pro-vided at bolted connections through a sheet metal base if

the base is not reinforced with sliffeners or is not capable oftransferring the required loads.

Where weak-axis bending of cold-formed steel supports isrelied on for the seismic load path, such supports shall bespecifically evaluated.

Components mounted on vibration isolators shall have abumper restraint or snubber in each horizontal direction,and vertical restraints shall be provided where required toresist overturning. Isolator housings and restraints shall beconstructed of ductile materials. (See additional design forcerequirements in footnote b to Table 13.6-1.) A viscoelasticpad or similar material of appropriate thickness shall be usedbetween the bumper and components to limit the impactload.

Expansion anchors shall not be used for non-vibration iso-lated mechanical equipment rated over 10 hp (7.45 kW).

EXCEPTION: Undercut expansion anchors are permitted.

The supports for electrical distribution components shall bedesigned for the seismic forces and relative displacementsdefined in Sections 13.3.1 and 13.3.2 if any of the followingconditions apply:

a. Jp is equal to 1.5 and conduit diameter is greater than2.5 in. (64 mm) trade size.

b. Trapeze assemblies supporting conduit, and bus ducts orcable trays where /,, is equal to 1.5 and the total weight ofthe bus duct, cable tray, or conduit supported by trapezeassemblies exceeds 10 Ib/ft (146 N/m).

c. Supports are cantilevered up from the floor.d. Supports include bracing to limit deflection.e. Supports are constructed as rigid welded frames.f. Attachments into concrete utilize nonexpanding insets,

power actuated fasteners, or cast iron embedments.g. Attachments utilize spot welds, plug welds, or minimum

size welds as defined by AISC.

For piping, boilers, and pressure vessels, attachments to con-crete shall be suitable for cyclic loads. . .«&»>«

f * ' \For mechanical equipment, drilled andjgrouted-in-placejan-chors for tensile load applications shall use either expansivecement or expansive epoxy grout. u^ - u;U»4inu,

13.6.6 Utility and Service Lines. At the interface of adjacentstructures or portions of the same structure that may moveindependently, utility lines shall be provided with adequateflexibility to accommodate the anticipated differential movementbetween the portions that move independently. Differential dis-placement calculations shall be determined in accordance withSection 13.3.2.

The possible interruption of utility service shall be consideredin relation to designated seismic systems in Occupancy Cate-gory IV as defined in Table 1-1. Specific attention shall be givento the vulnerability of underground utilities and utility interfacesbetween the structure and the ground where Site Class E or F soilis present, and where the seismic coefficient SD$ at the under-ground utility or at the base of the structure is equal to or greaterthan 0.33.

13.6.7 HVAC Ductwork. Seismic supports are not required for\ / HVAC ductwork with /,, = 1.0 if either of the following conditions

is met for the full length of each duct run:

150 ASCE 7-05

a. HVAC ducts are suspended from hangers 12 in. (305 mm) orless in length. The hangers shall be detailed to avoid significantbending of the hangers and their attachments.

b. HVAC ducts have a cross-sectional area of less than6 ft2

(0.557m2).

HVAC duct systems fabricated and installed in accordance withstandards approved by the authority having jurisdiction shallbe deemed to meet the lateral bracing requirements of thissection.

Components that are installed in-line with the duct system andhave an operating weight greater than 75 Ib. (334 N), such as fans,heat exchangers, and humidifiers, shall be supported and laterallybraced independent of the duct system and such braces shall meetthe force requirements of Section 13.3.1. Appurtenances such asdampers, louvers, and diffusers shall be positively attached withmechanical fasteners. Unbraced piping attached to in-line equip-ment shall be provided with adequate flexibility to accommodatedifferential displacements. f*—*^-/—

13.6.8 Piping Systems. Piping systems shall satisfy the require-ments of this section except that elevator system piping shall sat-isfy the requirements of Section 13.6.10.

Except for piping designed and constructed in accordance withNFPA 13, seismic supports sha|llnot|be required for other pipingsystems where one of the following conditions is met:

1. Piping is jupgortedjyjxxjhangers^ hangers in the piperun are 12 in. (305 mm) or less in length_fornjhe_top_ofthe pipe to the supporting structure; hangers are detailedto avoid bending~oF the hangers and their attachments; andprovisions are made for piping to accommodate expecteddeflections.

2. High-deformability piping is used; provisions are made toavoid impact with larger piping or mechanical componentsor to protect the piping in the event of such impact; and thefollowing size requirements are satisfied:

a. For Seismic Design Categories D._E._or F where I,, is_greater than 1 j), the nominal pipe sizgjhall_bgj_in. (25mm) or less. Fir* 4 U-fc ^ft^V '•

b. For Seismic Design Category C, where /,, is greater than1.0, the nominal pipe size shall be 2 in. (51 mm) or less.

c. Por_Seismic Design Categories D^§,_oj_F_wjiere_/£_isequal to 1.0, the nominal pipe size shall be 3 in. (76 mm)or less.

13.6.8.1 ASME Pressure Piping Systems. Pressure piping sys-tems, including their supports, designed and constructed in ac-cordance with ASME B31 shall be deemed to meet the force,displacement, and other requirements of this section. In lieu ofspecific force and displacement requirements provided in ASMEB31, the force and displacement requirements of Sections 13.3.1and 13.3.2 shall be used.

13.6.8.2 Fire Protection Sprinkler Systems in Seismic DesignCategory C. In structures assigned to Seismic Design CategoryC, fire protection sprinkler systems designed and constructed inaccordance with NFPA 13 shall be deemed to meet the otherrequirements of this section.

113.6.8.3 Fire Protection Sprinkler Systems in Seismic DesignCategories D through F. In structures assigned to Seismic De-sign Categories D, E, or F, the following requirements shall besatisfied:

1. The hangers and sway bracing of the fire protection sprinklersystems shall be deemed to meet the requirements of thissection if both of the following requirements arc satisfied:

a. The hangers and sway bracing are designed and con-structed in accordance with NFPA 13.

b. The force and displacement requirements of Sections13.3.1 and 13.3.2 are satisfied.

2. The fire protection sprinkler system piping itself shall meetthe force and displacement requirements of Section 13.3.1and 13.3.2. j -/.$

3. The design strength of the fire protection sprinkler systempiping for seismic loads in combination with other serviceloads and appropriate environmental effects shall be basedon the following material properties:

a. For piping and components constructed withSuctile rna-terials (e.g., steel, aluminum, or copperV90 percentpfthe minimum specified yield strength.

b. Forfthreaded connections) in Components constructedwith\ductile materials, 70 percent)of the minimum spec-ified yield strength^

c. For piping and components constructed withjnondUctile^imaterials (e.g., plastic, cast irqn^or^ceramicsX' 10 percent/'of the material minimum Specified tensile strength.j"

13.6.8.4 Other Piping Systems. Piping not designed and con-structed in accordance with ASME B31 or NFPA 13 shall complywith the requirements of Section 13.6.11.

13.6.9 Boilers and Pressure Vessels. Boilers or pressure ves-sels designed in accordance with ASME BPVC shall be deemedto meet the force, displacement, and other requirements of thissection. In lieu of the specific force and displacement require-ments provided in the ASME BPVC. the force and displace-ment requirements of Sections 13.3.1 and 13.3.2 shall be used.Other boilers and pressure vessels designated as having anIP = 1.5, hut not constructed in accordance with the require-ments of ASME BPVC shall comply with the requirements ofSection 13.6.11.

13.6.10 Elevator and Escalator Design Requirements. Eleva-tors and escalators designed in accordance with the seismic re-quirements of ASME A 17.1 shall be deemed to meet the seismicforce requirements of this section, except as modified in the fol-lowing text.

13.6.10.1 Escalators, Elevators, and Hoistway Structural Sys-tem. Escalators, elevators, and hoistway structural systems shallbe designed to meet the force and displacement requirements ofSections 13.3.1 and 13.3.2.

13.6.10.2 Elevator Equipment and Controller Supports andAttachments. Elevator equipment and controller supports andattachments shall be designed to meet the force and displacementrequirements of Sections 13.3.2 and 13.3.2.

13.6.10.3 Seismic Switches. Elevators operating with a speed of150 ft/min (46 m/min) or greater shall be provided with seismicswitches. Seismic switches shall provide an electrical signal in-dicating that structural motions are of such a magnitude that theoperation of ctevators may be impaired. The seismic switch shallbe located at or above the highest floor serviced by the elevators.The seismic switch shall have two horizontal perpendicular axesof sensitivity. Its trigger level shall be set to 30 percent of theacceleration of gravity. Upon activation of the seismic switch,

Minimum Design Loads for Buildings and Other Structures

elevator operations shall conform to requirements of ASMEAl 7.1, except as noted in the following text.

in facilities where the loss of the use of an elevator is a life-safety issue, the elevator shall only be used after the seismic switchhas triggered provided that:

1. The elevator shall operate, no faster than the service speed.

2. Before the elevator is occupied, it is operated from top tobottom and back to top to verify that it is operable.

13.6.10.4 Retainer Plates. Retainer plates are required at the topandbottorn of the car and counterweight.

13.6.11 Other Mechanical and Electrical Components.Mechanical and electrical components, including distribution sys-tems, not designed and constructed in accordance with the refer-ence documents in Chapter 23 shall meet the following:

1. Components, their supports and attachments shall complywith the requirements of Sections 13.4, 13.6.3, 13.6.4, and13.6.5.

Where mechanical components contain a sufficient quan-tity of hazardous material to pose a danger if released, andfor boilers and pressure vessels not designed in accordancewith ASME BPVC, the design strength for seismic loads incombination with other service loads and appropriate envi-ronmental effects shall be based on the I'o) lowing materialproperties.

a. For mechanical components constructed with ductilematerials (e.g., steel, aluminum, or copper), 90 percentof the minimum specified yield strength.

b. For threaded connections in components constructedwith ductile materials, 70 percent of the minimum spec-ified yield strength.

c. For mechanical components constructed with nonductilematerials (e.g., plastic, cast iron, or ceramics), 10 percentof the material minimum specified tensile strength.

d. For threaded connections in piping constructed with non-ductile materials, 8 percent of the material minimumspecified tensile strength.

152 ASCE 7-05