Page 317 - Advanced Design Examples of Seismic Retrofit of Structures

306 Advanced Design Examples of Seismic Retrofit of Structures

TABLE 5.9 Expected Shear Capacity of Beams
2
2
Profile F ye (kg/cm ) A w (cm ) V CE (ton)
2INP240 2360 33.4 47.3
INP240 2360 16.7 23.64
2IPE140 2360 10.52 14.9
IPE140 2360 5.26 7.44
IPE180 2360 7.73 10.94
IPE240 2360 11.78 16.68

(5.24)
Q CE ¼ V CE ¼ 0:6:F yE :A w
where:
A w ¼nominal area of the web;
t w ¼web thickness; and
h ¼distance from inside of compression flange to inside of tension flange.
The expected shear capacity of beams is presented in Table 5.9.

5.6.1.2 Columns
The lower-bound strength, Q CL , of steel columns under axial compression shall
be the lowest value obtained for the limit states of column buckling, local flange
buckling, or local web buckling. This lower-bound strength is determined based
on Eq. (5.25).
Q CL ¼ P CL ¼ 1:7 F a A (5.25)

where F a ¼allowable axial compressive stress which is based on Eq. (5.26),in
which F yLB is replaced by F y .
" 2 #
1 1 λ
F a ¼ 1 F y
F:S 2 C C
λ λ
3
F S ¼ 1:67 + 0:375 0:125
C C C C (5.26)
s ffiffiffiffiffiffiffiffiffiffiffiffiffi
r ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 6
2
2
2π E 2 π 2:1 10
C C ¼ ¼ ¼ 131:94
F y 2275
KL
λ ¼
r