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GSA Program Features


GSA allows the user to work in any units. Several standard sets of units are provided to cover most situations; these may be customised if required. Different units can be used in different views on the data and output is annotated accordingly.

Data Input

For regular structures a Data Generation wizard will allow the user to specify the structure in terms of few key parameters and automatically generate the model data. For more complex structures structural geometry and loading data may be input through either the graphical data generator (“Sculpt”) or a more traditional spreadsheet format.

Sculpt enables all structural geometry to be rapidly generated and edited on the screen using a cursor controlled by a mouse. Dynamic viewing makes it possible to adjust the model as required. When the structure is complete, all loading may be similarly generated and displayed diagrammatically. Structures of complexity varying from simple to large skeletal frame models can be generated and complex 2D element meshes can be generated using the automatic mesh generation facilities.

The alternative spreadsheet method incorporates many useful features for the generation and copying of numerical data. Text input is normally specified by selection from a list of available items rather than by entering numeric codes.

The two data generation methods are linked so that they can be used side by side.


When an analysis is requested the data are checked for inter-module consistency. If errors are detected, a report is prepared and the program returns to the data editing options; if not, the program proceeds with the analysis with progress being reported to the screen throughout.


Steel Design results are not stored. Instead, they are calculated as required to produce the diagrams, contours or text output requested by the user, using the input data and analysis results to perform the calculations.

Concrete Design is handled in two ways in. For beam design the user can export a model to AdBeam for design. For slab design the required areas of steel are calculated and displayed as graphical or text output as requested by the user, based on the analysis results.

All types of Design results are only available if the corresponding analysis results are available.


Output can be in the form of tables showing the numerical results, graphics showing diagrams or contours and charts showing plots of one variable against another for some analysis results

The units used for output may be specified interactively as standard or non-standard and default to those used for input.

The axes directions in which results are given may be global, local (nodal or element) or user-defined. User-defined axes may be Cartesian or cylindrical.

The format of numeric output may be specified in terms of either significant figures or decimal places.


The graphics facility in GSA is designed to feel spontaneous in response to the commands of the user. Various single key commands have the effect of producing standard views, adjusting the orientation, scale and content of the drawn structure, windowing, zooming, labelling and annotating the display. Dynamic viewing and animation of results provide powerful tools to aid the engineer in understanding the behaviour of the structure.

The resulting graphics may be exported to an image file or sent direct to a printer.

Tabular Output

A wide choice of results may be displayed on the screen or printed.

Output results available include displacements, forces, beam stresses, reactions, and analysis details. Tabular output can contain summaries of maximum and minimum values present in the selected output.

Data from tables can be transferred to and from spreadsheets using the standard cut and paste facilities. The GWA file (ASCII data file) is written as a tab-separated file to facilitate input into spreadsheet programs.