In the 2015.j version, the "Justification of seismic action report" generated by CYPECAD has been extended to include the following sections:
- Combined seismic shear per floor
- Combined seismic shear and equivalent seismic force per floor
- Seismic shear percentage resisted per type of support and per floor
- Seismic shear percentage resisted per type of support at starts
The maximum calculated responses for each mode, for floor forces and shears, are combined using the CQC mode superposition method to obtain the total effect in each analysis direction. The results are displayed in graphs and tables.
This information allows users to assimilate the dynamic analysis that has been carried out to an equivalent static analysis. This data is both informative and descriptive, and provides a graphical and intuitive reference on the behaviour of the structure. Nonetheless, bear in mind that the program carries out a complete dynamic analysis with modal expansion for the design.
Another new feature displayed in the report is the percentage of seismic shear that is resisted depending on the type of the support. Many seismic codes classify resistance systems as "frame-type", "wall-type" or "mixed" depending on the seismic shear each element resists.
The structural systems are classified and then a numerical value is attributed to each category which reflects the energy absorption and dissipation of the structure, which in turn reduces the defined seismic action.
The percentage seismic shear that is resisted by column-type supports and the percentage resisted by shear wall-type supports are provided in the new section of the report, for each loadcase, per floor and at starts. This data allows users to check the type of resistance system used in the analysis and verify that the reduction in the applied seismic action, based on this classification, is adequate.
