Page 314 - Advanced Design Examples of Seismic Retrofit of Structures

Example of a Steel Frame Building Retrofitted Chapter 5 303

FIG. 5.8 Plastic hinge characteristic of girders ridge in the sports building ( P UF 0:15).
P CL

Where evaluating the behavior of force-controlled actions, a lower-bound
estimate of the component strength, Q CL , shall be used. Q CL is the lower-bound
estimate of the strength of a force-controlled action of an element at the defor-
mation level under consideration and is defined as the mean minus one standard
deviation of the yield strengths, Q y , for a population of similar components [2].

5.6.1 Linear Static Procedure

5.6.1.1 Beams
The strength of structural steel elements under flexural actions shall be calcu-
lated in accordance with this section if the calculated axial load does not exceed
10% of the axial strength.
For bare beams bent about their major axes and symmetric about both axes,
satisfying the requirements of compact sections, L b <L p , Q CE shall be computed
in accordance with Eq. (5.20):
(5.20)
Q CE ¼ M CE ¼ M PCE ¼ Z:F ye