OS-E: 7000 Response Spectrum Analysis

Demonstrates the response of water filled elevated tank structure.

Response spectrum analysis is carried out to estimate the maximum response of a structure for a transient event. On a modal space when a response spectrum is specified as dynamic loading, estimate the maximum displacement and stresses as a response of the spectrum.
Figure 1. FE Model

Model Files

Before you begin, copy the file(s) used in this example to your working directory.

Model Description

The finite element model, as shown in Figure 1 is constrained at the bottom of the structure with all DOF’s fixed, modal damping with respect to natural frequency and frequency dependent dynamic loads are applied on the structure.
FE Model
Element Types
The linear material properties are:
Linear Material 1: STEEL
Young's Modulus (E)
2.1e5 MPa
Damping coefficient
Density (Rho)
7.9e-9 t/mm3
Linear Material 2: STEEL_SANDWICH
Young's Modulus (E)
3e4 MPa
Damping coefficient
Density (Rho)
9e-10 t/mm3


The maximum response of the structure is analyzed for the transient loadings.
Figure 2. Maximum Displacement of the Structure

Figure 3. Maximum von Mises Stress in the Structure