Design Principles
Beams are designed for main (longitudinal) reinforcement calculated for both sagging and hogging moments on the basis of the section profile and parameters defined in the Design Criteria menu. There are two load envelope curves used for beam design; a seismic envelope and a non-seismic envelope.
Longitudinal and transverse reinforcement is designed by the program based on the forces generated in the Concrete Analysis module. Forces used for design are adjusted according to the procedure given in the design code which is outlined below:
- Get beam gravity and lateral forces from analysis;
- Adjust M for plastic redistribution (gravity load cases only);
- Adjust M, V, N for seismic effects for Transfer Beams (seismic load cases only);
- Calculate combinations and generate envelopes;
- Modify beam end shears using the adjusted M in the combinations (for load combinations which include seismic loads). Adjust rest of curve using the factor given in the table.