Saad Pervez

UBC97 1630.5: Concentrated force at top, Ft, becomes zero if time period is 0.7 seconds or less. My statement was not 100% correct. Apologies.

There is no lower limit for T but there is an upper limit for Maximum V, so even if the time period calculated by ETABS is significantly lower than Ta, code provisions for maximum base shear would govern and the calculated value of T would be ignored. Similarly, no vertical distribution of force would take place for a small time period hence your design would still be in reasonable FOS limits.

What are the dimensions of the beam you designed? Stiffeners are required to control local buckling of the web and flange.

@Ahsan Kazmi Net My on interior columns is less than My on exterior columns because of the presence of beams on both sides of interior column. Try to solve one interior column and one exterior column manually.

I think this should be the only criteria for determining diaphragm type.

Eccentricity

Turn off auto meshing if it's on and manually mesh the area in question. Avoid a very small element.

The only technical reference you will find is an article by William R. Osgood titled "The double modulus theory of column action", published in 1935. I doubt you'd want to explain double modulus theory in your university presentation.

The stiffening ribs should've been in a direction perpendicular to the main beams?

Concrete on the building exterior treated to an exterior finish e.g. paint is classified as concrete exposed to weather or not? I am facing this problem in placing the reinforcement, the exterior will be painted and weather protected, should I follow the cover requirements of concrete exposed to weather or not?

You're absolutely correct. Standard practice in the industry from what I've seen so far is to only calculate the R & U value based on a single typical section. (even Dubai Municipality's site has the same calculations). But in reality, presence of openings will adversely effect the thermal resistance of the whole building envelope. Masonry laid as shown in the video will create a thin layer with minimum resistance between each layer and if calculated properly. The thermal insulation will be much less. Example from personal experience: the R value for a typical section was 2.27 but when the whole building envelope was taken into account using weighted average, the value reduced by almost 40% to 1.32.

Not an expert but AFAIK cable analysis is only possible with the advanced version of SAP2000. So make sure you're using that. And just a suggestion, why not take the axial force results from SAP2000 and check the cable manually?

EI and EA factors deal with the residual stresses which remain in the structure, which will result in a change in effective stiffness. The technical note for AISC360-05 Direct Analyis Method states that: " Reduction factors to section EI and EA are automatically applied by the program .... However, as soon as a design is run the reduction factors are used and remain in the model. This means that the first time the model is analyzed and designed, users must iterate between design and analysis at least one additional time. Thereafter, both analysis and design will have reduction factors applied automatically. " You can try changing your "Analysis Method" from Preferences>Steel Frame Design Preferences to "Effective Length" and see how that works out.

The default Insertion Point is always Top Center. If you're only working with gravity loads there should be no change in the end moments. However if you provide an offset to both End-I and End-J in the dialog box AND uncheck the "Do not transform stiffness matrices" checkbox at the bottom, there will be an additional moment on the column below for gravity loads. If there are lateral loads present, only then the moment on the column below (or any fixed support for that matter) will change to the magnitude of "force times beam depth/2". ALWAYS remember to uncheck the "Do not transform stiffness matrices" checkbox if you want the program to consider the effect of insertion points.