Story deflection = Cd(0.11") = 5(0.11) = 0.55 inches (14mm)

Allowable Deflection = 0.02(33.3' = 8" (203 mm) > 0.55" (14mm), OK

)

(From Table 6-1)

D-1 *Check for Performance Objective 2A (Safe Egress).*

This performance objective uses the same ground motion as the Life Safety Performance Objective (1A).

The structure is a one-story building analyzed by the ELF procedure, and therefore, the seismic effects,

QE, in step B10 may be scaled up in a linear manner.

D-2 *Determine the pseudo lateral load, V=C*1C2C3SaW

C1: Modification factor to relate expected maximum inelastic displacement to displacements calculated

for linear elastic response. (per FEMA 273 Section 3.3.1.3)

T0 = SD1/SDS = 0.75

T = Fundamental period of building = 0.25 seconds

C1 = 1.5 (0.25-0.10)/(0.75-0.10)*(0.5) = 1.38

C2: Hysterisis modification factor, from Table 5-2;

C3: Modification factor to account for P-delta effects.

Assume that the building exhibits positive post-yield stiffness.

C3 = 1.0 for positive post-yield stiffness.

V = (1.38)(1.3)(1.0)(1.0g)(635 k) = 1139 k (5066 KN)

D-3 *Determine seismic effects.*

The seismic effects in Steps B-4 through B-9 are scaled up by the factor R x C1 x C2 x C3.

Scale factor = (6)(1.38)(1.3)(1.0) = 10.76

D-4 *Determine the combined load effects.*

The shear force to the wall segments are scaled up by the factor 10.76 and the resulting shear demand is

checked against the shear strength multiplied by the appropriate m-factor from Table 7-4.

The moment frames will be analyzed for the load combination 1.2D + 0.5L + E, where the E term

represents the seismic actions determined from step B.10 scaled up by 10.76 (Note: the term 0.2SDS x D is

not scaled up by 10.76, therefore, the load factor for the dead loads is 1.2 + 0.2 = 1.4)

H3-52

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