520
V. Iancu and L. Cindea
Table 1 Amortization
reduction factor
β [%]
B
AASHTO
ASCE 1–10
Eurocod 8
≤2
0.8
0.8
0.8
5
1.0
1.0
1.0
10
1.2
1.2
1.2
20
1.5
1.5
1.6
30
1.7
0.7 or 1.8
1.9
40
1.9
1.9 or 2.1
2.1
50
2.0
2.0 or 2.4
2.3
in which: S a is the spectral acceleration, T the period and β represents the damping
factor.
In Table 1, we present the amortization reduction factor values extracted from
AASHTO [8], ASCE 1–10 [9] and Eurocode 8 standards.
3 The Shape of the Friction Pendulum
Figure 6 shows the normalized elastic response spectrum for the horizontal components of the ground movement in areas where the seismic hazard is characterized by
the absolute accelerations a g = 0.20 g and a g = 0.16 g under the seismic and terrain
conditions of the Banat Romania region, with β 0 = 3 for the corner values T B =
0.07 s, T C = 0.7 s and T D = 3 s.
Knowing the important class of the building, its total weight and the behavior
factor, using the relation below, we can calculate the cutting forces acting on it:
F t = γ 1 · Sd(T 1 ) · m · λ
(7)
Fig. 6 Crusty sources in the
Banat area