Not sure why your RSA is showing larger base shear than the base shear calculated by equivalent lateral force method. When you calculated the static base shear did you limit the structure's period to maximum allowable by the code?
Since it's a two story building there are two modes of vibrations. Natural frequency for the first mode will be lower than the 2nd mode, hence the effective stiffness of the building will be lower for the 1st mode as well. since, the stiffness is directly related to structure mass and frequency...
As hokie said, the load will be distributed based on the proportion of the stiffness. If you know how to calculate the beam stiffness (hint: may consider slightly stiffer than simple span beam in each direction)then the distribution factor for flexure for each direction beam can be calculated...
I agree with hokie66. Since under a design earthquake, a plastic hinge could undergo enough straining to get into the range of strain hardening, it is very important to also consider possibility of strain hardening that could deliver additional member capacity during capacity protection design...
How many columns do you have per pile cap, more than one for a 24 pile cap? As the others said, for a single column cap, the cap will be a cantilever beam. However, if you have more than one column then the cap will behave like a continuous beam between columns. In order to determine moment...
IF you are analyzing the structure for seismic, then the code specified damping is 5%. However, damping value should be less for dynamic analysis for wind, machinery or wave induced fatigue. Under those types of loading the structure essentially remains elastic and so the damping is relatively...
This has been in the seismic design code for sometime now. I believe, the value is selected from experience and testing based on material and structural elastic and post elastic behavior.
If this is a single story portal frame building, then either the base of the column or connection between the roof and columns can be considered pinned and designed as such, the other end should be considered fixed. The structure will be unstable if both ends are considered pinned. You may also...
Critical damping means that a system will not vibrate at all, on the other hand 0% damping means that the system will keep on vibrating without any reduction in the amplitude or frequency. 5% damping means that the damping is 5% of critical damping. 5% damping is low but still should reduce the...
Your beam should be designed considering interaction of both bending and axial loads. You should use the load combinations from Chapter 2 and 12 (as applicable) of ASCE 7. Load combination specific load factors should be applied to bending and axial. Don't forget to add the vertical component...
I believe your interpretation is correct. When failure of a non-essential component may damage an essential or structurally important part of the structure, the attachment for a non-essential component must be designed adequately per the code requirement. An example may be, if a non-essential...
I believe, the short period acceleration, Sds that is included in UFC should match with that in ASCE 7. Therefore, you should be fine if you use Sds from ASCE. Component Importance factor (Ip) can also be taken from ASCE.
If the buildings are connected, they should be analyzed as connected considering due torsional irregularity for seismic analysis. For certain type of irregularity, static seismic analysis is no longer valid, a dynamic analysis may be required.
If the buildings are physically separated, they can...
If possible, it may be wise not to mix different load resisting systems (moment frame and braced) in the same direction. Although, having moment frame system in one plan direction and braced frame in the orthogonal direction of the building should be fine. However, if different systems will...
As Hokie said, it may not be desirable to detail an exterior beam to column connection with no top reinforcing or very little development length to act as pinned connection. Following should be kept in mind when deciding on such detail:
1. Will the connection see any load reversal due to...
