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Hello, I have recently joined a structural engineer, and trying to get myself familiar with the norms of practice, so I have some basic questions which I haven't been able to get answers of sufficiently. After modelling the structure in ETABS I'm trying to find out how to interpret the values of shear and torsion reinforcement given in design outputs. I have tried to find the answers by codes, manuals but haven't succeeded. Even asking my colleagues haven't given a satisfying answer, as everyone has his/her own way of interpreting these values. Thanks,

W.salaam. Assuming that the heading on the link below refers to a version of Safe, the Non-Liner Version would do. Which version do you have? See the link below for complete features: http://www.comp-engineering.com/products/SAFE/analysis.html Thanks.

Ratio of flexural capacity of Beam/column is computed to preclude the formation of plastic hinges in columns for obvious reasons, refer to section 21.6.2 of ACI 318-11. Sum of flexural capacities of column at a joint should be 1.2 times the capacities of beam framing into the joint in particular direction. Etabs alerts user when the ratio exceeds; if it does not alert, it means either you are ok, or you have not activated corresponding seismic category (I think it calculates for category D E & F) for which this capacity needs to be computed. When capacity is exceeded, we can increase the size of column, or reduce the size of beam, or play with reinforcement of members. It has nothing to do with redistribution of moments; If both end of column will yield, during a seismic event, in a particular story, structure will most probably collapse. In a frame, that is resisting lateral loads, you cannot take away the ability of beam to develop negative moment; if you do not provide top reinforcement, it will not be called a moment resisting frame, and will not resist lateral loads..

Assalam o alekum Providing bracings in the building greatly reduces lateral diaplacements can we provide concrete bracings? or what property we should assign to brace element a beam or a column?,I modelled a concrete brace element in ETABS but Etabs donot design it for axial compression or tension

I have attached tutorials that will show you how to setup ETABS model for dynamic analysis. Go through all tutorials. There are lucid and self explanatory. OneDrive-2014-03-09.zip

You can find solved examples in the books such as Dynamics of Structures by Anil k Chopra, and Seismic and wind design of concrete buildings by S.K. Gosh and David Fanella.

Its more than that. You have to see what seismic zone your building lies and have to select the appropriate level of ductility and over-strength. I would recommend skimming through ACI Chapter 21. I have also attached some documents pertinent to the discussion that will help you develop a better understanding of aforesaid. Go through read them and if you have any question post in the forums Goodluck! How do Beam-Column Joints in RC Buildings Resist Earthquakes.pdf How do Columns in RC Buildings Resist Earthquakes.pdf How to make building ductile for Good Seismic Performace.pdf How do Earthquake Affect Reinforced Concrete Buildings.pdf What is seismic design philosophy of Buildings.pdf