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try making pattern live load factor to 0.

I am working on a building with quite high loading. live load :300 psf Super Dead :90 Psf The problem in my etabs result are quite unusual for me.I got more reinforcement in bottom as compared to negative in continuous beams. In the analysis, moment diagram is not showing such irregularity. need help form seniors.

sir , you were very much right . I got a normal pattern of my results. As it is confirmed from CSI ETAB (When nonzero Pllf is assigned to a frame object, positive design moments are calculated assuming a simply supported condition under live-load application. While this does affect design moments, analysis moments are not affected) https://wiki.csiamerica.com/display/kb/Pattern+live-load+factor

Dear all; I have prepared some procedures that in need to your evaluation according to your experience judgement. I am saying that the following procedures that I will mention will be trusted after your comments that agree or disagree. The procedure: 1. I get results from tables------> story drift as in pict.1. 2. Let us take one floor as a sample.For that floor we read the results of drift in x-direction as the maximum of all load combinations's results that contain earthquake i.e six load combinations as shown in pic.2 . 3. Do the above for y-direction. 4. As a result the for 4th floor; Drift-x = 0.001986 and Drift-y = 0.001812. 5. Now what are the values we get and how to use it. These values coming from ETABS are representing the difference in elastic displacement between the floor and the floor beneath or up divided by the floor height.(Please correct me if I am wrong). 6. Now to get the the seismic drift values from inelastic response we multiply the above drift by 0.7 *R . As an example let us say R=4.5 , then seismic drift-x =0.00625 and drift-y= 0.0057. 7. These values now are ready to compare with ACI code limitations, Assuming fundamental period of structure=0.5 second: story seismic drift limit =2.5% * story height 8. As you may see our story drifts either in x or in y are less than 2.5 %. Regards