Ultimate Strength Design Principles (USD)
(a) Reduced earthquake loads corresponding to the structural system ductility capacity are automatically determined for the projected performance target.
(b) Linear earthquake calculation of the structure is made automatically under reduced seismic loads. The reduced internal forces of the elements obtained from these calculations are automatically increased with D, strength excess coefficient, in cases specified by the regulation.
(c) Element strength demands are automatically compared with the determined internal force capacities.
(d) The relative storey drifts obtained from the earthquake calculation are compared with the limits specified by the regulation and automatically determined results are reported.
(e) It is automatically indicated by reports that the strength demands and relative floor displacements are below the specified limits, if there are insufficiencies, the user is warned.