Dynamic Analysis for RSTAB 9

The Modal Analysis add-on for RSTAB 9 is a powerful tool that facilitates your analysis of natural frequencies and mode shapes for beam structures. It imports all necessary input values directly from RSTAB and provides powerful eigenvalue solvers to determine up to 9,999 eigenvalues. The features include the import of masses from load cases, the definition of additional masses, the adjustment of the stiffness matrix, and the option to define several modal analyses for different masses or stiffness modifications.

Various eigenvalue solvers are available for the calculation, which can be selected depending on the size of the model. Once the calculations are finished, the results with the eigenvalues and mode shapes are listed in tables and can be displayed graphically and animated.

Forces of nature are a natural enemy of every structural engineer. But don't worry, you can perform your calculations in advance in the event of an earthquake. The Response Spectrum Analysis add-on will help you with this. It performs seismic analyses using the multi-modal response spectrum method. You can create the response spectra required for this in compliance with the standards, or user-defined. The program use them to generate the equivalent static forces.

The add-on includes even more for you; for example, an extensive library of accelerograms from seismic zones. You can use them to generate the response spectra as well. Note: The seismic analysis using the multi-modal response spectrum analysis requires the analysis of natural vibrations in the Modal Analysis add-on.

The Time History Analysis add-on allows you to perform dynamic structural analysis of external excitation. You can define various excitation functions in tables or as a function of time. The time history analysis is performed using the modal analysis or the linear implicit Newmark analysis.

The core features include the combination of user-defined time diagrams with various load types, the application of several independent excitation functions, and the graphical display of results in the calculation diagrams. The input of the necessary force-time diagrams is arranged intuitively, and allows for a user-friendly configuration of the analysis parameters. This add-on is characterized by user-friendly input options and the ability to calculate multiple analyses simultaneously, which provides engineers considerable flexibility when evaluating the dynamic behavior of structures.

Using the Pushover Analysis add-on for RSTAB 9, you can analyze the seismic actions on a particular building, and thus assess whether the building can withstand an earthquake. The Pushover Analysis add-on allows you to analyze the deformation behavior of buildings subjected to a seismic action.

The capacity curve, which represents the nonlinear structural properties of a building, is calculated by applying a horizontal load distributed over the height and increasing it gradually. This curve is then compared to the seismic action, based on extensive libraries and the method specified in Eurocode 8, to determine the target displacement. The add-on provides you with the intuitive input and allows you to consider nonlinearities in irder to achieve realistic design.