Bentley Staad Pro V8i
http://preferredmode.com/2013/11/04/cliff/ STAAD.Pro allows structural engineers to analyze and design virtually any type of structure through its flexible modeling environment, advanced features and fluent data collaboration.
termly Flexible modeling is provided by a state-of-the-art graphical environment and the design supports over 70 international codes and over 20 U.S. codes in 7 languages.
An array of advanced structural analysis and design features are included such as nuclear certification for 10CFR Part 50, 10CFR 21, ASME NQA-1-2000, time history and push over analysis and cable (linear and non-linear) analysis.
Structural Analysis and Design (STAAD) is also some time referred as STAAD Pro. For Professional. As the name suggests it is a design computer program that deals with the designing of structure beams steel or concrete or any other material; generally STAAD and ETABS runs parallel with each other in design; it is used to do framing of the architectural drawing that is obtained from the architect, to determine the loading combinations; then the position of beams columns is decided after which their dimensions and steel requirement is calculated and checked by STAAD. STAAD works both ways if you give dimensions and steel percentages, it will analyze your structure and at the end even give you recommendations for the improvement in design.