Response Spectrum Load Cases






Enter the load cases, spectrum functions and loading directions for response spectrum analysis. The procedure for response spectrum analysis in Civil 2006 is outlined below. 1. Enter mass data using various ways provided in the Main Menu, Model>Masses. 2. Enter the number of modes and necessary data for eigenvalue analysis in Eigenvalue Analysis Control. 3. Define spectrum data to be applied in Response Spectrum Functions. 4. Set options related to response spectrum analysis in Response Spectrum Load Cases. 5. Perform analysis by clicking Perform Analysis or using the Main Menu, Analysis>Perform Analysis. 6. When an analysis is completed, analyze the results using load cases or load combinations with various postprocessing functions from the Results menu. 







From the Main Menu select Load > Seismic > Response Spectrum Load Cases. 





Spectrum Functions Select predefined design spectrum functions, which will be used to define a number of response spectrum load cases. A same spectrum from a code may result in a number of spectrum functions depending on the damping ratio. Therefore, this becomes useful when the user wishes to define a number of spectrum functions based on different damping values in a structure. Apply Damping MethodDamping Method : Define the damping property of a structure. Mass and Stiffness Proportional Correction by Damping Ratio : When a single spectrum is selected, a modifying equation is used to adjust the spectrum to apply to each mode having a corresponding damping ratio. Note 1 Note 2 Interpolation of Spectral DataSelect the method of interpolating the response spectrum load data. Linear : Linear interpolation method Logarithm : Logscale interpolation method Description Enter a short description OperationEnter new or additional response spectrum analysis load cases Enter the above entries and click .
Modify previously entered response spectrum analysis load cases Select a response spectrum analysis load case from the list in the dialog box and click .
Delete previously entered response spectrum analysis load cases Select a response spectrum analysis load case from the list in the dialog box and click .
In addition to the spectrum functions and the loading conditions of the response spectrum, access the following functions to enter additional data required for a response spectrum analysis: : Eigenvalue Analysis Control... is invoked to check dynamic properties of a structure. : Response Spectrum Functions... is invoked to define spectrums. 

