Figure C-7 Three Story Shear Wall Structure

DOE-STD-1020-2002

The following provides an example application of this simplified nonlinear analysis

procedure for estimating F for a concrete shear wall structure.

For purposes of this illustration, a three-story structure with the properties shown in

Figure C-7 will be used. This figure shows the weights, W, at each story, the elastic stiffnesses,

k, and the ultimate capacities, V , for the walls between story levels. This structure has a

fundamental frequency f of 8.25 Hz.

Assuming a damping parameter β of 7%, for a reference l.0 g NUREG/CR-0098 median

spectrum (Reference C-15), at f equal to 8.25 Hz the elastic spectral acceleration is:

S A ( f , β ) = 1.86 g

(C-11)

and the elastic response of this structure is given in Table C-8. For this reference spectrum

response, the ratio of the elastic demand to the capacity ranges from l.02 for the first story wall

to l.32 for the second story. Thus yielding will initially occur in the first story wall, and the

elastic displaced shape at the onset of yielding is given by δ in Table C-8. Note in Table C-8

that the minimum value of V/VR (i.e., l.02) is used to calculate δQ since this corresponds to the

first element which reaches yield (i.e., level l).

Figure C-7 Three Story Shear Wall Structure

C-36