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The author reminds me of Taher Shah (self-proclaimed musician).

The standard loading is Dead, Super-dead, Live, Wind, Seismic, and any maintenance loading. Loading is related to the "use of structure". You can apply load based on use based on ASCE 16.

Walaicum Salaam, In General we design Structures for, Dead Loads, Live Loads, Super dead loads, Collateral loads. Wind Loads, Seismic Loads and, Snow loads (For Special Regions). There are some special cases for pump rooms or Parking areas or Storage tank etc. You have to consider those as well. Regarding Load combinations, You can go bothways. I suggest you define your own Combinations as to get aware of things. I Suggest you to read ASCE-10 before you go in to modelling process. Regards !!

Remember the advice given by Einstein, "In theory, theory and practice are the same. In Practice, they are NOT". Get exposure to practical courses whilst you are studying...check out the post below as a starter....

many engineers in pakistan use this practice when modeling a beam in etabs , that if beam is fail in shear and torsion than they just change the torsion modifier from 0.35 to 0.001 , and then redesign that beam , after designing that beam appear to be pass in shear and torsion , also showing zero r/f required for this particular beam. i want to know that is this the right way to model beam, does code provide such kind of solution ,or it has no meaning.

justified and reasonable practice as explained above the concept of equilibrium torsion

Hi Waqas, I have seen your updated post. What you have quoted in correct and as per ACI recommendations. What I am trying to highlight is that we don't need to worry about compatibility torsion for typical beam-column, two way slab concrete frame structures because - and I will quote my above reply here: The approach of 0.001 is used because ACI minimum design recommendations are too conservative for compatibility torsion for beam-column two way slab structure (what we have in Pakistan 99% of the time). That is why you never see any serviceability failures due to compatibility torsion (the other reason could be the tendency to over-reinforce structure but lets focus on this one for now). You can follow the guideline but those who don't follow it (like myself), do it for the reason explained above. The difference here is the same as difference between laws and traditions. Laws are there but people tend to incline towards tradition. So, probably we can blame our innate tribalism for following such stuff and not code.

In my understanding these are NOT 2 different methods; This is just a differentiation; There are two torsions; 1. Compatibility torsion (where redistribution of moments take place) like slab on beams 2. Equilibrium torsion (where there is no path available for redistribution of moments, like a cantilever slab resting on a beam) These are not two different methods of analysis in ACI or ETABS. This is just to distinguish the cases. That is why it does not matter in ETABS because in ETABS loads will follow the paths that is available. So does not matter if it is case 1 or 2, apply J modifiers but watch for slab moments. Also make sure your detailing handles all these issues. For example if the beam is torsionally too stiff as compared to slab, it will take more moment as compared to slab, and if you are applying less J modifier to beam then make sure the detailing also follows the same approach. (try to increase bottom reinforcement of slab).

They are doing it right. It depends on you. It is the beauty of the structures that they will behave the way you designed them. When reducing the torsion modifier for beams that are failing to a value approx equal to 0 then watch for the increased moments in slabs. If you put the reinforcement in slab for additional moment then it is ok! It depends upon the relative stiffness of beam and slab that how much load beam will take (Torsion, moment etc).