c.

follows steps outlined in Table 4-5 for Performance Objective 1A.

A-1 *Determine appropriate Seismic Use Group. *Per Table 4-3 of the manual, the building is allowed

to incur moderate structural damage. Therefore, it is a standard occupancy structure with a Seismic Use

Group of I.

A-2 *Determine Site Seismicity. *The site seismicity for this example from the MCE maps is assumed

as:

Ss = 1.40g, and S1 = 0.50g.

A-3 *Determine Site Characteristics. *For the purpose of this problem, a stiff soil condition was

assumed corresponding to a site classification of ` lass D'per Table 3-1 of the manual.

C

A-4 *Determine Site Coefficients, F*a and Fv. From Tables 3-2a and 3-2b for the given site seismicity

and soil characteristics, the site response coefficients were interpolated as follows:

Fa = 1.00

(Table 3-2a)

Fv = 1.50

(Table 3-2b)

A-5 *Determine adjusted MCE Spectral Response Accelerations:*

SMS = Fa(SS) = 1.00(1.40) = 1.40

(EQ. 3-1)

SM1 = Fv(S1) = 1.50(0.50) = 0.75

(EQ. 3-2)

A-6 *Determine Design Spectral Response Accelerations:*

SDS = (2/3)SMS = (2/3)1.40 = 0.93

(EQ. 3-3)

SD1 = (2/3)SM1 = (2/3)0.75 = 0.50

(EQ. 3-4)

The approximate period of the structure (based on T = 0.1N, where N = number of stories) is:

Tapprox = 0.1N = 0.1(3) = 0.3 < 0.5

(EQ. 5.3.3.1-2 FEMA 302)

Since Tapprox < 0.5, and because the structure is less than 5 stories in height, Equations 3-5 and 3-6 must be

checked in the short period range:

SMS [ .5Fa

1

(EQ. 3-5)

SM1 [ .6Fv

0

(EQ. 3-6)

Therefore,

SMS = 1.4 < 1.5(1.00) = 1.5

SM1 = 0.75 < 0.6(1.50) = 0.9

A-7 *Determine Seismic Design Category. *With SDS = 0.93, SD1 = 0.50, and a Seismic Use Category

of I, enter Tables 4-2a and 4-2b to obtain a Seismic Design Category of ` '

D.

A-8 *Select Structural System.*

Gravity: Reinforced concrete hollow core slabs to span between transverse bearing walls.

Lateral: As permitted by table 7-1 of the manual;

Transverse direction:

Special reinforced concrete shear walls.

Longitudinal direction:

Special reinforced concrete moment frames.

A-9 *Select R, ς, & C*d factors.

H2-8

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