PSI - Issue 44

Diego Gino et al. / Procedia Structural Integrity 44 (2023) 1435–1442 Diego Gino et al./ Structural Integrity Procedia 00 (2022) 000 – 000

1441

7

b)

a)

a)

λ=0.10 λ=0.15 λ=0.20 T p =0.20s T p =0.10s T p =0.15s T p =0.05s . λ= . λ= . . . T . .

λ=0.10 λ=0.15 λ=0.20 T p =0.20s T p =0.10s T p =0.15s T p =0.05s λ . λ . λ=0. p . s p . T p . p .

P f [-] (50 years) P f [-] (50 years)

P f [-] (50 years) P f [-] (50 years)

r [m] r [ ]

r [m]

Fig. 7. Representation of the seismic reliability curves associated to the deck response referred to the abutment for Td =1s (a), Td =4s (b).

6. Conclusions This study relates to the seismic reliability of multi-span continuous deck bridges equipped with single concave friction pendulum (FPS) devices. A wide parametric study has been carried out taking into account several bridge configurations (i.e., differentiating the vibration period of the RC pier in elastic field, the isolating system period and the ratio between the pier and the deck mass). The seismic reliability assessment leads to the following results: i. With reference to the pier, the fully operational and operational limit states are fulfilled in all situations demonstrating the effectiveness of the seismic isolation devices. ii. Concerning the isolator devices (i.e., of the deck) the seismic reliability decreases with the increase of the radius of curvature of the FP device due to the high seismic hazard of the considered site. With reference to assessment/design of multi-span continuous deck bridges located in areas with significant seismic hazard, the achieved results are helpful to define rules for the preliminary design of the isolation system in line to target reliability levels associated to the related reference life. Appendix A. Summary of the seismic records adopted for reliability analysis:

Vs 30 [m/sec]

M [-] 6.7 6.7 6.7 7.1 7.1 6.5 6.5 6.9 6.9 7.5 7.5 7.3 7.3 6.9 6.9 7.4 6.5 6.5 6.5 7.0 7.6 7.6 6.6 6.5 6.9 6.9

R [km] 13.3 26.5 22.9 41.3 26.5 33.7 29.4 98.2 53.7 82.1 9.8 31.4 40.4 35.8 11.2 15.1 22.7 77.5 39.5 20.2 21.3 21.0 32 86 8.7 46

PGA m [g]

Year 1994 1994 1994 1999 1999 1979 1979 1995 1995 1999 1999 1992 1992 1989 1989 1990 1987 1987 1987 1992 1999 1999 1971 1976 1980 1979

Earthquake Northridge Northridge Northridge

Recording Station

Fault type

1 2 3 4 5 6 7 8 9

Beverly Hills - Mulhol Canyon Country-WLC LA – Hollywood Stor

356 309 316 326 685 275 196 609 256 276 523 354 271 289 350 724 192 208 194 312 259 705 316 425 496

Thrust Thrust Thrust

0.52 0.48 0.36 0.82 0.34 0.35 0.38 0.51 0.24 0.36 0.22 0.24 0.42 0.53 0.56 0.51 0.36 0.45 0.21 0.55 0.44 0.51 0.21 0.35 0.94 0.18

Duzce, Turkey Hector Mine Imperial Valley Imperial Valley Kobe, Japan Kobe, Japan Kocaeli, Turkey Kocaeli, Turkey

Bolu Hector Delta

Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip Strike-slip

El Centro Array #11

Nishi-Akashi Shin-Osaka

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Duzce Arcelik

Landers Landers

Yermo Fire Station

Coolwater Capitola

Loma Prieta Loma Prieta Manjil, Iran

Gilroy Array #3

Abbar

Superstition Hills Superstition Hills Superstition Hills Cape Mendocino Chi-Chi, Taiwan Chi-Chi, Taiwan San Fernando

El Centro Imp. Co. Poe Road (temp) Westmorland Fire Stat. Rio Dell Overpass

Thrust Thrust Thrust Thrust Thrust

CHY101 TCU045 Tolmezzo Bisaccia

LA - Hollywood Stor

Friuli, Italy

Irpinia

-

Montenegro

ST64

1083

Thrust