israr_sari

In context of live load "For how long a load need to be remained on a structure to characterised it as a sustained load?"

if you want to make pedestals for the tank over your Foundation (as you said Raft), then you will apply this load as point loads on your foundation pad.

Etabs Doesnot Fail beams in Flexure normally..... Even sometimes it go beyond Rho maximum but at the same time it adds same amount of additional reinforcement (over Rho maximum value) on the opposite face of beam to maintain ductility behaviour of beams.... this what i have observed... anyone is open to comment.

what i assume ..... construction is precast and failure occur because of inadequate seating of precast panels..... precast slab panels even seems fine after coming down. sometimes unbalanced load after such failure could leads to progressive collapse.

these Cracks are in your Plaster because of improper curing .....

@Ahmed Waqar Settlements is within limit which is about 0.8". And Allowed is 2" Subgrade of Modulus is 186 kip/ft3 with bearing capacity of 8.01 Kip/ft2. @Rana well Rana i tried to play with meshing .. no-matter what size i adopted stresses were over and above the limit (there was very less effect of meshing). only stresses came down when i didn't use any kind of meshing. Which is definitely wrong approach... so finally i concluded that i can not bring down these stresses with str ess averaging so need some other solution. MODEL-C1&C2 28-6-2018.bmp

@Ayesha @Hafsa Azmat thanks for both of you. @Areeb you can check in the picture that i have attached above. basically it is spreaded all in the middle of raft.

Dear Safeians I ma working on a 22 Storey Building. we have assume a Raft foundation of 5' for it. Net bearing capacity after overburden relief is 8kip/ft2. And i am getting 10Kip/ft2 soil pressure under service loads at some locations. one of my friend said use stress averaging to minimise the values as these soil pressures are nodal results of finite elements. do somebody have any clue how to do that using safe .. or Excel. stress distribution.bmp

@sameersaleem Any reference for this combination...................?

Dears Rana, One huge difference even i have noticed, that is short beams failure under earthquake loadings. short beams that are usually safe in Version 9.7, sometimes fail in version 16. This is a common phenomenon in Earthquake analysis. The earthquake shear is either to be multiplied by 2 as per ACI 318-05 or the shear is to be derived from moment capacity at the ends. The earthquake shear has to be added to the gravity shear resulting in total shear which should not exceed the ultimate shear capacity of the beam (including reinforcement).

I am trying to investigate the effects of soil structure interaction on the rigidity of multi-storey RCC framed structures and other parameters (under the action of earthquake loading.) In order to accomplish that i am using sap 2000 for the modelling. what i need to do i have to model soil support as (uni directional as well as three dimensional) : liner elastic Non-linear elastic Elasto-plastic i am little bit confident with first two that i can do something (still suggestions and comments would be appreciate) but i am struggling to model the behaviour of Elasto-plastic soil. is there anyone have experience of modelling that in sap 2000? even any literature that could be helpful for the modelling would be appreciate. One more thing for the analysis purposes i am using linear static analysis approach as it is widely using by engineers throughout the world. (how far my assumption is correct: i need your valuable comments) thanks and my best regards

How to import multilevel raft foundation from etabs to safe. main designer has designed it as a raft foundation with a bearing capacity of 150 kn/m2 but after the site development and excavation we found a hard strata that can with stand with 250 kn/m2(as per the soil report). as total depth of raft is 1 m that is too much for 5 storey car parking, i want to modify it with 250 raft overall with inverted panels under column. but i am not able to import that multi level foundation reactions as a one file in Safe. because in etabs u can only export one storey . please give your helpful suggestions.

yeah i find that but how to analyze and design that slab............. I need some literature regarding the design

RAMADAN KAREEM.....

Dear engineers, i have a concrete shed with arched type roof (barrel vault). i am not sure how it will behave structurally (Membrane or Shell). i need your help to start it if following ways. need some reference for basic structural design methodology of such structures. your opinion which software can do this better (Etabs , sap or any other) how one can do the modeling......... you can share your work if you had already done.