Analysis Output

In the majority of cases, users will make use of only a fraction of the wealth of results that can be obtained from SeismoStruct, since it is common for the response of a limited selected number of nodes and/or elements to provide sufficient information on the performance and response of the structure being analysed. Therefore, in the Output module, users are given the possibility to trim down their analysis output to the necessary minimum, thus reducing both hard-drive consumption as well as post-processing time and effort. This can be achieved through the following output settings:

Frequency of Output
If a frequency value equal to zero is adopted, then output is provided at all analysis steps where equilibrium has been reached, including those corresponding to step reduction levels. If a frequency value equal to unity is used instead, then step reduction level output is omitted. This is the default behaviour, since users are usually interested in obtaining results which are in correspondence with the initial number of increments/steps that have been defined in pre-processing. However, if the latter is not the case (e.g. the analysis loading has been split into a very large number of increments just to ease convergence), then a frequency value n larger than unity can be employed, with output being provided at every n equilibrated steps.

Output Nodal Response Parameters
Users can specify the nodes for which output of nodal response parameters (support forces, displacements, velocities and accelerations) will be provided. The user may select all or none of the nodes by right-clicking and choosing Select All or Select None from the popup menu that appears. Pre-assigned node groups can also be used for easier selection. Note, however, that if not all nodes have been selected for output, the deformed shapes of the structural model cannot be plotted in the Post-Processor.

Output Element Forces
Users can specify the elements for which output of internal forces (axial/shear forces and bending/torsional moments) will be provided. The user may select all or none of the elements by right-clicking and choosing Select All or Select None from the popup menu that appears. Pre-assigned element groups can also be used for easier selection.

Output Stress/Strain peaks and Curvature
Users can specify the elements for which output of curvatures and stress/strain peak values (maxima and minima) will be provided (note that such output refers to the Integration Sections of inelastic frame elements). The user may select all or none of the elements by right-clicking and choosing Select All or Select None from the popup menu that appears. Pre-assigned element groups can also be used for easier selection. Note that this options should be used with care since choosing to output curvature and stress/strain peaks for all elements of a large structure may result in the creation of extremely large (hundreds of Mb) output files.

Output Stress and Strain Values at Selected Locations
If users are interested in following the variation of stress and strain of a particular material, located at a given sectional point in the Integration Sections of inelastic frame elements, then they may define output Stress Points. It is noted that these sectional points are only used for monitoring purposes, and their stress values are not considered in the calculation of the internal element forces. Users may select the element and integration section from the drop-down menus. The coordinates on the section and the material's name are determined by the program, after the user selects graphically the area to be monitored.

Note: In the Output module, there is also the possibility for the user to customise the real-time displacement plotting that is shown during the analysis of a structure, by choosing the node and degree-of-freedom to be considered. For better visualisation, users are advised to keep the program defaults, which employ the absolute top displacement plotted against base shear for static analysis, and the total drift (difference between top and bottom displacements) plotted against time value for dynamic analysis.