component under the design loading condition. In

this document, *Q*CE is defined as the nominal

(3) Design actions.

strength, *Q*N, multiplied by 1.25, unless otherwise

(a) Deformation-controlled actions shall be

noted in Chapters 7 through 10.

calculated according to Equation 6-2:

(b)

Force-controlled actions.

Force-

(6-2)

controlled actions in structural or nonstructural

components

or

elements

are

those

responses

where:

generally characterized by the Type 3 curve and in

some cases by the Type 2 curve in Figure 6-1.

Acceptance criteria for the capacity of these

and earthquake loads.

components or elements are provided in Chapter 7,

and the components or elements shall be evaluated

in accordance with the provisions of this paragraph.

The value of force-controlled design action, *Q*UF,

defined in ASCE 7.

need not exceed the maximum action that can be

developed in a component considering the nonlinear

behavior of the structure. In lieu of more rational

Deformation-controlled

actions

in

structural

analysis, design actions may be calculated according

to Equation 6-4a or 6-4b. Note that *Q*E has been

components shall satisfy Equation 6-3:

determined from the pseudo-lateral load, *V*, defined

(6-3)

in Paragraph (2) above as the basic spectral response

force, *S*aW, modified by *C*1, *C*2, and *C*3 to represent

where:

the expected deformation in the building.

In

Equation 6-4b, *Q*E is divided by the modification

factors to restore *Q*E to a force-controlled action. The

component or element demand

force delivery factor, *J*, in Equation 6-4a, represents

modifier to account for expected ductility of the

deformation associated with this action at selected

an approximation of the additional reduction in the

Performance Level (see Chapters 7, 8, 9 and 10).

force delivered to a force-controlled component or

element by a yielding component of the seismic

framing system.

or

element

at

the

deformation

level

under

consideration for deformation-controlled actions.

(6-4a)

For *Q*CE, the expected strength shall be determined

considering all co-existing actions acting on the

6-8

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