DESIGN SPECIFICATIONS FOR HIGHWAY BRIDGES - IISEE

u
y
a 1
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ (10.2.3)
y
where
μa : Ductility capacity of the Reinforced Concrete Columns
δu: Ultimate displacement of the Reinforced Concrete Columns, specified in Section
10.3 (mm)
δy: Yield displacement of the Reinforced Concrete Columns, specified in Section 10.3
(mm)
α : Safety factor shown in Table 10.2.1
Table 10.2.1 Safety Factor in Calculating Ductility Capacity of an Reinforced Concrete
Columns Resulting in Flexural Failure
Safety Factor α in Safety Factor α in
Seismic
Calculation of Ductility Calculation of Ductility
Performance to
Capacity for Type I
Capacity for Type II
be Verified
Earthquake Ground Motion Earthquake Ground Motion
Seismic
Performance
3.0 1.5
Level 2
Seismic
Performance
Level 3
2.4 1.2
2) For a pier of shear failure after flexural yielding or shear failures, the Ductility
Capacity shall be taken as 1.0.
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