or

more,

the

mathematical

model

shall

be

redesigned, and the pushover procedure repeated

unless the overdesign can be justified as being cost-

maximum inelastic displacement to displacements

effective or otherwise beneficial.

calculated for linear elastic response.

1.0 for *T*e ≥ *T*s

(2)

Target displacement.

The target

=

displacement *t for a building with rigid diaphragms

at each floor level shall be estimated using an

[1.0 + (*R *- 1) *T*s/*T*e]/*R *for *T*e < *T*s

=

established procedure that accounts for the likely

but need not exceed:

nonlinear response of the building.

Actions and

C1 = 1.5 for Te < 0.10 sec.

deformations corresponding to the control node

displacement equaling or exceeding the target

C1 may be interpreted between Te = 0.10 sec and

displacement shall be used for component checking

Te = Ts.

in Chapter 7.

The procedure for evaluating the

target displacement is given by the following

equation:

spectrum, defined as the period associated with the

transition from the constant acceleration segment of

2

the spectrum to the constant velocity segment of the

*t = *C*0 C1 C2 C3 Sa

(5-5)

4Π 2

spectrum.

where:

ratio of elastic strength demand to

calculated yield strength coefficient. See below for

additional information.

building in the direction under consideration

effect of hysteresis shape on the maximum

using one of the following:

displacement response. Values for *C*2 are established

in Table 5-2.

the first modal participation factor at

the level of the control node

=

Modification factor to represent

increased displacement due to dynamic P-) effects.

the modal participation factor at the

For buildings with positive post-yield stiffness, *C*3

level of the control node calculated using a shape

shall be set equal to 1.0. For buildings with negative

vector corresponding to the deflected shape of the

post-yield stiffness, values of *C*3 shall be calculated

building at the target displacement

using Equation 5-7.

the appropriate value from Table 5-1.

5-14

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