UmarMakhzumi

There is Atkins Etabs guide that has information on importing such data into Etabs. You can download it from this thread.

It is same as designing concrete walls but, You need to consider what your modulus of elasticity will be, as your concrete might be highly air-entrained or would be with lightweight aggregate. Also, your modulus of rupture would determine the minimum reinfo in concrete.

Normally, in a structural model, we only model elements of a structure that contribute to gravity/ vertical or lateral stiffness of a structure. Concrete insulated panels, unless load bearing should be modeled. If it is load bearing, then most likely you are not working on a frame structure. Cheers.

W.salaam Why do you want to model them?

You should go with cracked section properties as Section 1910.11.1 of the UBC provides modified properties to be determine lateral story drift. If your lateral force resisting system includes a shearwall, here is what yo should do, determine if the tensile stresses in the shearwall are greater than the modulus of rupture (7.5 *sqrt f'c) of the concrete (these would be the S22 stresses if the local x axis is in line with the global x axis). If so then the section is cracked. Use a value of 0.7Ig for serviceability. For the same model, apply crack section properites to shearwalls(use 0.35Ig or whatever is agreed upon) for strength design as they would reflect a true redistribution of loads.

It tells you about frequency of different modes in different units(Units as in Hz and radians). Frequency can be used to get time period. Time period is an important parameter and you can use it for a lot of things. Since people do computer analysis & design together, like you are doing now, so the software does everything for you. Mostly, time period in useful in knowing the stiffness of memeber and is related to forces it will attract under seismic and wind in case of non-static analysis.

General Basement Wall Design. take a unit strip, if your basement wall has a slab on top, you can treat it as a propped cantilever with Ko (Coefficient of Static earth pressure: as wall cant move to Ka state for failure).. If cantilever, design for lateral loading with Ka(Coefficient of active earth pressure). Significant Vertical Load If you have significant vertical load design it as a beam column and use ACI wall provision for min/ max reinforcement.

It says in the snapshot. Frequency 1/time Circular Frequency 1/Time*2*pi

I dont have Etabs. There should be something you are missing out.

Beams? I doubt. The most economical solution would be a PT flat slab or flat plate that would help get a thinner slab with least formwork. Two way slab supported on beams ka to PT karne ka I am not sure. Agar aisa ho to much rebar congestion and you wouldnt be able to get the best buck for your slab. Do some research and post your "summary" here. I am attaching a sample design calc. Hope it helps. Thanks. Timesaving-2WayPost-IA.pdf

Story Shear/ Story displacement

I have done something related in RISA.. Post what are you working on..what is the design problem?

thanks for the heads up. I was away. Just came back. Good work Rana.. I have made some changes.. I hope that will work Cheers

Like Rana said, I will just add one more thing. I remember that Live Load only needs to be considered in Mass Source if its a warehouse, or LL=100psf or more. See UBC, for clarification, there is something about the warehouse or 100 psf requirement.

there are a lot of books available that can help you design a PT Slab. The classical one is from Collin & Mitchelles. PT Slabs can be cost effective only if you can justify their use. Like, if you have large spans, and you want to keep a thin slab, PT is the option. That will also help you have smaller foundation and save cost there too. You need to have skilled labour, or contractor for that job. I doubt if there are a lot of contractors in Pakistan that do cast in place PT Slabs. What kind of application do you want PT to use?? shed some light on what you up to?

yeah!

great question Rana.. a lot of ppl dont even bother thinking about it.. cheers

you can use them with time history analysis, thats what I perceive.. EDs book has a chapter on it.

You should define separate load cases. It would help you understand mode shapes, assign scale factors so that modal mass to be 90% or whatever code criteria is, and make your combos compatible too.

thumbs up

You should do it manually if its a retaining wall for a building/ basement. I would say only use software for this case, when you have to do a retaining wall structure.

its name of a book/ document.

I did one and the reference I used was , Design of Blast-Resistant Buildings in Petrochemical Facilities There is a solved example in it , calclations are simpe. You need to assume the load/ explosive weight and distance from load, calculate the shockwave velocity and proceed. I will check if I can find my calcs, but I am not sure I have it with me or not. Regards,

It doesn't specifies, it just says hollow slab 20 " thick. There might be.

here is an excerpt from on of my fav books on structural design, I read it some 3 years back, and it always reminds me how we structural engineers can exploit material properties to achieve robust designs.