Civil Engineering Reference
In-Depth Information
FX+ for DIANA
+2.45007e-001
+2.14204e-001
+1.83400e-001
+1.52596e-001
+1.21792e-001
+9.09886e-002
+6.01849e-002
+2.93812e-002
-1.42253e-003
-3.22263e-002
-6.30300e-002
-9.38337e-002
-1.24637e-001
-1.55441e-001
-1.86245e-001
-2.17049e-001
-2.47852e-001
17.4%
15.7%
13.6%
10.6%
11.1%
9.1%
7.5%
5.2%
2.1%
2.1%
1.3%
1.3%
1.0%
0.7%
0.6%
0.3%
Y
X
[UNIT] N, mm
[DATA] Structural Eigenvalue, DtX (V), Mode 2(12.0734)
Figure 7.18
Mode shape 2 at 12.07 Hz.
of 2%, the Rayleigh damping parameters, α and β,
have been evaluated to
be 5.762 and 0.00024, respectively, from Equation (7.8). These values are
used as input parameters to the model when it is necessary to introduce
2% damping. Two sets of results for the linear model have been obtained -
one for the 'no damping' condition and the other with 2% damping. Two
sets of results were further obtained in the case of the nonlinear concrete
model (using nonlinear material properties for cracks as discussed above)
for the no damping condition and with 2% damping. Some of the mode
shapes corresponding to dominant frequencies in the lateral (
X
) direc-
tion obtained from the modal analysis of the finite element model are
shown in Figures 7.18, 7.19, 7.20 and 7.21. The results were obtained
in terms of acceleration response of the system and are illustrated in the
next section.
7.2.4 Wavelet-based analysis of numerical results
The responses were obtained from the numerical model in terms of the
acceleration response of specific nodes in the system. These nodes are
