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Sir g in first Pic where the column is failing in the window there SHORT COLUMN effect is also visible ...what you think as we the length of the column is reduced due to the walls which is highly unfavorable in earthquake region because then the shear forces are high in that region and they cause such shear failure so this must also be kept in mind that the length of column is not restricted in that way that it produces short column effect......

asad R is structural participation factor for the base shear.we make our structures in two different ways one that whole structure bears the base shear force and still remains in the elastic range there is no plastic hinge formation or non linear range... and other way is that we design our structure such that some part of base shear is resisted by structure and remaining part is shared by the ductility of the structure and structure goes into non linear range and hinges are formed. what we prefer that our structure behave the second way so it some part remains in the elastic range and other part in plastic.Plastic hinges are only preferred in the higher zones like you mentioned 3 or 4.In low zones we don't make plastic hinges as it makes structure uneconomical so we do more elastic and little bit ductile structure.. So the value of R is kept low as this value is divided by the base shear and the force which comes out is taken by the structure and remaining is taken by the ductile part of structure....In normal zones structures are low ductile and value of R is less. Now if we go to the higher zones like 3 or 4 what we want is that our structure should be flexible and it resist all the seismic forces and should not fail at any stage. So SMRF structure is preferred and Strong column weak beam structure is designed. So when we take value of R like 8 or 9 it means that base shear divided by R the value we get is resisted by structure and the remaining force is very big goes to the ductile part of the structure so just to get that much ductility or flexibility in the structure plastic hinge phenomena is introduced in the structure. What happens in the plastic hinge that our structure gets all the deformation and it goes to the plastic hinge region but it don't fail or fall down but this is only in very severe cases or very high zones. In plastic hinge we keep very close reinforcement at the beam column joint what happen with this reinforcement that concrete is more confined as we know that in concrete structures failure only occurs due to the cracking of concrete and steel fails at very very late stage so with this extra shear reinforcement we make structure flexible such that large deformations occur but no failure of structure. So i hope that you will get it now and Plastic hinges are made in SMRF structures as they are specially designed to resist severe seismic actions. and plastic hinges are formed that our structure should not fail at any cost it should go in non linear range ... I suggest you to read some thing about the push over analysis and non linear hinges in structures ... I hope that now you are much clear what i mean but still if you have any doubts please donot hesitate to ask...

this is really a controversial question! based on what i have been doing uptill now here is the summary! if you have very hard rock support use fixed if the soil is weak and fear of liquification use pinned remember its always conservative to use pin support for column design as all the moment will be redistributed to column but for foundation design if you make the support fixed you have to design it for moment just a rough rule:- for isolated foundations use pin for mat or combined footings use fixed

to asadishfaq! Well i think you better post this in software issues section where i have already started a thread called SAFE/ETABS/CSI Problems/issues!

Asad i think you have to look that is there any room or terrace what kind of structure on the slab .... But keep in mind that you have to use inverted beams for that as this will reduce loading to some extend compared to the one in which you design normal hanging beam....

And sorry one more thing i like to mention here that i understand the concept which you explained to waqar i think but here it is important to tell him that such rft deatiling is very very poor for structures and he can see why it is poor .....Shear stirrups long. bars everything is not according to seismic requirements....what you say..

There is no tutorial that will land you with your project in a week. Unfortunately you have to study!

Bahria Town Icon Tower-2 comprises of 40 floors for residential purpose. its my final year project doing through beg associates

This building promises to be tallest in Pakistan when completed. Project Description: Bahria Town Icon consists of two towers which are identical up to 8 floors i.e. 7 basements for car parking and 1 ground floor. Tower-1 comprises of 70 levels for office space and Tower-2 comprises of 30 floors for residential purpose. Client: AAA Partnership (Pvt.) Ltd. - Karachi. Location: Karachi. Architect: Arshad Shahid Abdullah (Pvt.) Ltd. - Karachi. Engineer: ESS-I-AAR - Karachi. (Structural) Beg Associates - Karachi. (Structural) WSP - UAE. (Structural) CFA: 2,230,500 m2; (24,000,000 ft2) Estimated Cost: USD 162.5 Million (PKR 13 Billion) START DATE April, 2010.