WR1

From the table it sounds like this X= x direction Y= vertical direction Z = y direction that makes sense for wind loads as the vertical reactions (uplift due to wind) is -101, -61, -80 and -40 (units?) and at the same time wind loads in horizontal x direction are: -61, -52, 26 and -17 but what doesnt make sense is why there are no reactions in y direction which is Z in your case??? there is no wind loading applied in that direction? ---------------- The next step is to combine these loads according to chapter 9 load combinations of ACI remember here we will make both service combinations for bearing pressure check and ultimate combinations for reinforcement design of footings then combine all these loads and check bearing pressure and reinforcement design by hand or by any software

Well Zaib it depends! If you have assumed pin base then it means moment at base = 0 and you have only the vertical load reaction. If this is the case then the footing area required Areq = P/180 where P is kN and Areq is in m². Then you can convert this area into a square footing or a rectangular footing as you need. Or if you have moments things get more complicated so you can either do it manually or choose any software; like SAFE, PROKON or MIDAS. I am not aware of PROKON, so I would tell you what to do in SAFE. Start a new model and make isolated foundations (preliminary sizing) and put a node in the center of footing and put the vertical reaction on this node. Run the analysis check the bearing pressure and see if the sizing is ok. If not then change footing sizes and re-run. After it design it on SAFE for reinforcements.

Yeah thats a better option!

I vote against this change of colors...Its too dark and eye constraining, looks more familiar with civilea.com. Green color is good but make the backgroud white...You know green and white....White background is best for online reading

Select the columns, and goto Assign>Line>Releases

carry out moment distribution method example to have an idea of relative stiffness....

It behaves in between simply supported and fixed...depending upon the relative stiffness of beam and column..If column stifness is much more, then the beam would behave as fixed (near to fixed) and pin if column stiffness is very less...

I think local building code of Pakistan is based on american codes. Other members can shed light on this.

So the difference is 3 feet. Keep your model as simple as practical. There must be a deep 3 feet beam between these 2 levels or captive columns. How will you design them? I would have modelled them at two different levels to capture the seismic effect.

at the outset, i want to suggest that you DONT actually need to send .ebk file which you did in zip. .$et file is enough for anyone to review and check. The facility is in seismic zone 4 Make LL factor in p-delta = 1.0 (im leaving the question for you to research..why) You have made the base fixed, take care in the design of baseplates. (Bi-axial moments....how would you design it)? Coming back to your main question, When i ran the model, all of the members passed including the columns. (LOL). Is there something I am not getting? Check in your model, the effective length factors for columns and beams. They might need to be adjusted. I would assert that you should have made a simple 2d model of this and should have studied it properly before starting the 3d model. Its never too late, if you haven't done one yet. You can do it now. In 2 model, check how much are the reactions, column axial forces and drifts to have a FAIR idea about the structure you are dealing with. For drift, search in this forum. I have made a lengthy topic about building drifts. Just do the struggle to search it. I am surprised to see no WIND load on the structure as it would be more critical for uplift of foundations and drift (If seismic is not governing). Is that the reason? 0.25inch thick shell to model the slab? I would recommend to make it as thin as possible (to the point just near where ETABS does not start giving errors...try 5mm may be). This is to exclude any out-of-plane effects of the shell.

Please create a new section entirely dedicated to THE fem. I will send you my suggestion about the logo. For the rest of the changes, please go ahead. We need new attire and colors.

by the way why u like to connect slab to the underside of beams? beams are modelled as line elements and slab as area element....to connect it that way you need to model 3d beam elements not 2d elements...also make sure you understand the basics of FEM for connecting different types of elements to each other

Apply bands of concrete in wall in as many locations as possible (at lintel level and at dpc level for example). Provided that there is no fixity from roof to walls, walls would act as cantilever and that requires a fixed base (you need to look at foundations too). For wall design you could use australian standards. Seismic design is governed by post-yield behaviour and that is present in concrete buildings but for a masonry wall, equivalent static loads might not be sufficient.

1-Are you using dynamic analysis? Ritz of Eigen? 2-Are you using omega (overstrength factor) special seismic settings?

see PCA notes on ACI for example on ACI 318-08

See example of strain compatibility in any book (macgregor or nilson)....for example see column design in nilson

Its Heriot Watt University

In addition to what Makhzumi has said, I would like to add that:- 1) I am not sure if you have to apply soil properties to all of the mat layers, but what I would prefer is to draw drop panels (thick portions of the raft) and then draw the rest of raft (no overlapping). Then as your senior told you to draw thick slabs (stiff property) fro drawing columns over column points in SAFE. But remember do not apply soil properties to these stiff elements. Make thickness of these elements as 1m. 2) You will get concentration of soil pressure and moments near supports (near columns). But do not go for the maximum peak pressure or moments. For bearing pressure, take the contour value just at the face of the column (stiff elements you just have drawn in step 1). Do not read contour values at the edges of elements rather look for the value in the center. 3) For moments and reinforcement design, design for 1m wide strip and average the moments for 1m width. You can do this by applying design strips in SAFE in x and y direction of width = 0.5m and then replicating them every 1m to cover all of your raft. Then after running the analysis you can put in the numbers of bars or dia of bars and the intended spacing of bars to check what reinforcement you require. Do let us know if you find more problems.

looks like joint problem in masonry....is it masonry or concrete column?

not necessarily

Well i dont understand why in 2014 we still talk about codes from 90s. I mean its good to have the basis and background how codes developed but we should not be using the old methods.

well this is not always true. Last year I did a similar comparative study in Saudi for one of our projects. UBC-97 gave higher base shear due to the fact that the actual calculated base shear exceeds the maximum allowed value that is independent of time period. Buildings were in moderate seismic zones and the height of building where the actual base shear was less than the max base shear was 16m for concrete and 18m for steel structures. These buildings were low rise having 3 stories max. In IBC 2006/ASCE 05 maximum base shear formula has T and actual base shear is constant for all heights. That is the reason max base shear governed upto 14m height of concrete and 12m height for steel structures. In nutshell IBC 2006 gave us upto 64% reduction in base shear magnitude in concrete and upto 56% reduction in steel buildings as compared to that of UBC-97.

Yes, Moment 3-3 means beam or frame is bending ABOUT 3-3 axis. Dont worry how the bending moment diagram is forming, thats just text. In 2-d plane, the max peak moment will be in the direction of local 2-2 axis but actually your frame bends in 3-3.

What I have read about drift is that codes (Im talking about ASCE & ACI) intention is to limit all these three states; serviceability, damage, and collapse. Codes distinguish and set criteria only for horizontal component of drift (horizontal racking) whereas in a building vertical component of drift also exists. We have Damage Index to know the extent of damage that's been done. Damage Index takes into account the effect of both horizontal and vertical components of drift like shear strain. This is one of my favourites about drift. See the attachment. Dan Berding Thesis.pdf

Before I answering these questions I would like to know in which semester are you studying?