Issue 64

A. Eraky et alii, Frattura ed Integrità Strutturale, 64 (2023) 104-120; DOI: 10.3221/IGF-ESIS.64.07

0.3

with sma without sma

0.2

0.1

0

-0.1

-0.2 Opening ( m )

-0.3

-0.4

0

5

10

15

20

25

30

35

40

Time ( s )

(c) Figure 9: Comparison between the time histories of three hinges opening when using SMA and as–built bridge under the scaled 1989Loma Prieta record and period ratio ( ρ = 0.8), (a) Hinge 1; (b) Hinge 2; (c) Hinge 3. Fig. 10 shows MHD with various period ratios for the three openings of this bridge. It is clear from Fig. 10 that opening 3 is the most affected by existing SMA because the stiffness of the last frame of this opening is very small compared to others and, as a result, its frequency ( ω ) is very small, resulting in a large relative joint displacement, particularly at small ( ρ ).

g p

q

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

with sma without sma

MHD ( m )

0.4

0.5

0.6

0.7

0.8

0.9

Period Ratio

(a)

g p

q

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

with sma without sma

MHD ( m )

0

0.4

0.5

0.6

0.7

0.8

0.9

Period Ratio

(b)

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