PSI - Issue 44

Guglielmo Amendola et al. / Procedia Structural Integrity 44 (2023) 1427–1434 Guglielmo Amendola, Giuseppe Carlo Marano/ Structural Integrity Procedia 00 (2022) 000 – 000

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Table 1. Regression statistics for the friction and pier’s top displacement .

c 1

c 2

c 3

c 4

c 5

c 6

c 7

c 8

c 9

c 10

R

2

*

, (50 ) opt th

 

-269.040

-0.007

0.355

-7.192

34.315

-0.268

-43.211

5.814

-7.299

-19.247

0.830

(50 ) p th

u 

13.083

0.001

0.996

0.002

-0.250

1.228

-0.005

-14.680

0.266

-0.284

5.065

*

, (84 ) opt th

 

-1509.022

0.185

0.667

0.413

2.428

16.088

-0.299

1091.082

-7.452

7.959

-221.968

(84 ) p th

u 

46.442

0.006

0.986

0.007

-0.833

3.491

-0.012

-48.453

0.333

-0.846

16.290

d u  , which also corresponds to the

Fig. 3 shows the statistics for the normalized maximum deck displacement

) d u GM  decreases

maximum global response of the bearing placed on the abutment. The mean value, Fig. 3(a), (

*   increases. In addition, the values of

( ) d u GM  slightly increase for larger values of

  . The

significantly as

1

values of the dispersion ( ) d u   , represented in Fig. 3(b), are very low for low 1 *

  values due to the high efficiency

*   .

of the IM , and attain their peak for high values of

1

b)

a)

b)

 

 

 

Fig. 3. Mean value (a) and dispersion (b) of the normalized deck displacement d u  vs.  1 *

0.05 p T s  and for

  and d T for

0.1, 0.15, 0.2    .

5. Conclusions This work studies the seismic performance of multi-span continuous deck bridges isolated with DCFP devices by adopting a simplified 8dof system. A wide range of isolator and bridge properties is investigated throughnon dimensional parametric analysis, recording both the deck and pier maximum response. The uncertainty in the seismic input is considered by solving the equations of motion for a set of 30 different ground motions. The outcomes of the dynamic analyses have been then statistically treated by computing the geometric mean and coefficient of variation. This has allowed concluding that: regarding the pier performance, an optimal value for the sliding friction coefficient can be obtained by minimizing the pier maximum response, depending on the bridge and isolator properties; concerning the deck performance, the response decreases significantly as the sliding friction coefficient is larger.