January 17, 2019
RISAFloor & RISA-3D: Two Buildings on the Same Podium
RISAFloor is the RISA Building System’s floor design software which allows users to design with composite decks, elevated concrete slabs and more. When paired with RISA-3D, the two create a complete solution for the analysis and design of multi-story structures, including two buildings on the same podium.
Equivalent Lateral Force/Static Force Procedure
After the definition of slab edges and the application of diaphragms in RISAFloor, RISA-3D is used to determine the different lateral forces that need to be attributed to each individual diaphragm that exists at each elevation. These story forces can then be displayed graphically (as shown below) per diaphragm at each elevation.
If your building requires a dynamic analysis, mode shapes can be calculated and displayed in the same fashion as they are for a single structure. Similarly, building frequencies and mass participation’s are just as simple to retrieve by simply choosing “frequencies” or “mode shapes” from the Results Toolbar or the Results menu drop-down.
Intermixing Diaphragm Types
RISA also allows users to analyze with different diaphragm types (flexible, semi-rigid, rigid) at the same elevation of your separate buildings. Using RISAFloor paired with RISA-3D, engineers can analyze and design complex structures with this configuration. In addition, RISA-3D is fully capable of determining the behavior of different diaphragm types at the same elevation when separate perimeters and diaphragm types for each diaphragm are defined within RISAFloor. These disparate diaphragm types can then be shown graphically in order to review results and deflections.