No.of cycles of loading. Step of Sub Div: Choose the step option to time step of loading SubDiv to sub divide a 1/4 cycle into this many integer time steps. Spectrum: Select this Function Option to provide spectrum parameters for your time history loading. Time History Parameters Dialog:
Time Step: Specify a solution time step to be used in the step-by-step integration of the uncoupled equations. Damping: The following options are available for specifying damping: Damping-this is to be used for specifying a single model damping ratio which will be applied to all mode. The default value is 0.05. CDAMP – if a damping ratio has already been specified under CONSTANTS based on the type of material in the structure, the value may be used directly in time history analysis. Check this option for that purpose. MDAMP – we wish to utilise individual damping ratios for individual modes, that is achieved through the means of the MDAMP option. The first step to doing this is the specification of those individual damping ratios, as explained under section 5.26 .3 of the STAAD technical reference manual and is done graphically from the command-define damping menu. If this first step has been completed, the instruction to utilise MDAMP done by selecting this option shown above.