Hi Lisu,
The peak acceleration is different for the two load cases. However, the most significant source of the difference lies on the story range specification where one of the two load cases considers a higher range than the other.
Regards,
pkjr618
Typically, we'd like to assign a fixed end condition for beams that are part of the lateral load resisting system of our structures so that they will resist moments induced by lateral load such as wind and earthquake. On the other hand, we might want to assign a pinned end condition on beams...
Hi Blackstar123,
You're thinking way too much about this, IMHO. Secondary beam is just a term used by the program to help us draw the structure.
Thanks and best regards.
For your 8 storey bldg., you can get away with just the static base shear procedure if the seismicity in your area is average to none and some other things like structure regularity as well as consideration of the system used to resist the seismic forces. Consult your local code for these items.
I have not tried this approach. Can you clarify which article it is you're referring to? It seems I have not mentioned a specific article in my last post.
In general, you might expect to get the same magnitude of force distributed to the cores if they have the same magnitude of moment/torsional...
I am not familiar with the algorithm of the software for earthquake torsion but one piece of information I can give is that you could look at the moment/torsional arm of the cores if they are symmetrical with respect to the orthogonal axis. Moreover, if these cores have the same mass(for...
Hi Pawel27,
It would benefit the readers of your query if you would cite the method you used for calculating the base shear. Generally, each method used for estimating the static base shear has been adopted based on tremendous amount of earthquake research but due to factors that are not yet...
I have tried modet the wall as a stick model in ETABS. However, the auto-design process might not be applicable since the stick model is considered as a column and not a wall. You would have to design the wall manually using the forces from the analysis.
Good day all,
One benefit of using shells for concrete slabs in ETABS is that the program automatically considers T-beam action for all beams with shell elements properly placed on them. I use membranes mainly because it distributes the surface load assigned to it either one way or two way as...
Hi dadomago75,
I've taken your moment release suggestion into consideration. The lateral system is all frames by the way. I will have a separate model considering only the selected frames taking the seismic load and other columns with moment releases. The beams not considered in the lateral...
Good day all,
I am in the midst of modelling a R.C. 4-storey residential bldg and initial analysis suggests that the bldg. is very stiff when all of the frames are used as lateral force resisting elements (SMRF class, Zone 4). Moreover, the detailing requirement that the ACI code imposes on the...
