PSI - Issue 78

Laura Ragni et al. / Procedia Structural Integrity 78 (2026) 2094–2101

2100

0.25

0.25

displacement lost displacement experimental data

displacement lost displacement experimental data

0.2

0.2

0.15

0.15

0.1

0.1

0.05

0.05

0

0

displacement [m]

displacement [m]

-0.05

-0.05

-0.1

100

200

300

400

500

600

700

800

900

1000

0

2

4

6

8

10

t [s]

t [s]

(d) Fig. 7. Numerical simulation of the response during the release phase of test D1(a), D2(b), D3(c) and D4(d).

Table 3: Model parameters of the base-isolated building

k 1 [kN/m]

c 1 [kNs/m]

k 0 [kN/m]

c 0 [kNs/m]

G ( γ is ) [N/mm 2 ]

γ is [-]

Test

D1 0.96 D2 0.60 D3 1.24 D4 0.66

0.353 0.436 0.355 0.416

6137 9742 5406 8873

469866 9054 522650 9054 458421 9054 510421 9054

2349 2613 2292 2552

3.3. Simulation of test D3 with increased velocities In order to highlight the effect of lost displacement during the loading phase the numerical model has been used to simulate the test D3 with an increased velocity of the loading ramp. More in detail the loading ramp of test D3 has been imposed to the model with a velocity 10, 20, 40 and 100 times larger. Since the actual velocity is 0,175 m/s and correspond to a flow rate of 5 l/m, the increased velocity cases correspond to 1.5 m/s, 3.5 m/s, 7 m/s and 17.5 m/s and to flow rate of 50 l/m, 100 l/min, 200 l/min and 500 l/min respectively. In Figure 8 the first and the latter cases are illustrated.

(a)

(b) Fig. 8. Simulation of the response for different velocity of the loading phase: 10∙v (a) and 100∙v ( b)