Story Drift Questions

[Respawn]

I have a small question regarding my story drift results for sap 2000. I exported the joint displacements (Descending order U2) of a parking structure (Special concrete reinforced moment frame) in one direction. I then did the *Cd etc. to get to my drifts. Each story is within the allowable limit, but I'm concerned with my results. Shouldn't my results increase as I go down each story starting from roof level?

My results:
R: 0.8915 in
5: 1.444 in
4: 1.882 in
3: 2.028 in
2: 1.23 in

 

[JoshPlumSE]

Those are the story drifts, not the total displacement at those levels. Right? If so, that looks reasonably normal to me.... Provided there is something more rigid about that first floor. Shear walls in addition to the moment frame. A lower story height or such.

Note: One of the biggest challenges I see with parking garages is how to keep the inclined ramps of the garage to NOT take the seismic shear as if they were a giant brace. I wonder if that's what's happening with your model. If so, it may just be more noticeable on the 1st floor.