Structural Concrete - Hassoun

20.3 Analysis Procedures 813
Example 20.3 Equivalent Lateral Procedure
Determine the design seismic force and seismic shear force for a six-story concrete special
moment-resisting frame adult education facility building located in an area of high seismic risk where
S s = 1.5 g and S 1 = 0.6 g, on soil class B. The story heights are all 12 ft, and the story weights are all
1700 Kips. Check the lateral deformation of the structure. Building elevation is given in Fig. 20.5.
The δ xe is obtained from static elastic analysis using the design seismic force and is given as follows:
Floor Level
δ xe
6 1.26
5 0.98
4 0.71
3 0.46
2 0.24
1 0.06
W 6 = 1700 K
W 5 = 1700 K
W 4 = 1700 K
6 @ 12'
W 3 = 1700 K
W 2 = 1700 K
W 1 = 1700 K
Figure 20.5
Example 20.3: Building elevation.
Solution
1. Risk category III, I e = 1.25 (Table 20.1)
S s = 1.5 gS 1 = 0.6 g (Figs. 20.1 and 20.2)
Soil class B; so,:
F a = 1.0, Fυ = 1.0 (Table 20.2 and 20.3)
S MS = 1.5 g, S M1 = 0.6 g
SDC is D. (Tables 20.5 and 20.6)
(Eq.20.2a and 20.2b)
S DS = 1.0 g (Eq.20.1a)
S D1 = 0.4 g
( ) 2
(Eq.20.1b) =
3 × 0.6 g