UmarMakhzumi

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Please see the following topics: Thanks.

What does the word structure refer to in the above sentence? The structure and dampers (Complete System) or the structure only without damper? The damping of the structure should stay what it is. The damping of structure and dampers (Complete System) would change based on properties of damper used. 5% is also debatable. I have worked on some steel structure that support vibratory equipment and we have used 0.5% damping for steel system. I have also seen calculations for a huge off-shore project that was done by the company I was working at the time (2012), it supported huge compressors on steel platform and the damping was 2%. There is a lot of discussion that can go around deciding what percentage of damping should be initially used. Thanks.

Sustained is generally defined as something the structure would "always see". For process industry structure, sustained load is the load due to operation of the plant (Dead, Pipe Operating, Guide, Anchor) and transient would be wind and seismic. To answer your question, live load is never sustained. Its time bound by definition and its load factor represents that statistical probability of occurrence. So you should never classify a live load as sustained load unless specified otherwise by the Code or Client Specification that you are using. Hope that helps. Thanks.

Hi Yasir, I haven’t done pushover analysis but I have used links in SAP2000 to model soil frequency dependent response. I am trying to understand the objective of your question. Are you trying to figure out how much damping your structure would need to achieve a seismic desired response(deflection within limit) and based on that select a commercially available damper. Is this understanding correct? Thanks.

Individual Member deflections are generally considered relative to ends. There are cases where your are interested in global deflections like maixmum sway of pipe rack structure etc. Thanks.

Hi Hamza, Can you please elaborate how do you know ETABS isn’t transferring the forces? Did you do a manual check. Also are your deflected shapes consistent? We need to make sure that there is no error in modelling. Thanks.

Good Luck. I wish you all the best. Job hunting can be frustrating but keep the hopes up and eventually you will find something good. Thanks.

You need to check first if the code requires you to perform a modal response spectrum analysis or equivalent static analysis. If, your structure falls for modal response spectrum analysis, you do it and it helps you see which modes are attracting more mass and subsequently more force. That time period is independent of your equivalent lateral analysis as both are different methods. So, there is no point in taking information from modal analysis to use it in equivalent lateral analysis. Yes, modal analysis is necessary. Between equivalent static and response spectrum, use one method based on criteria provided by Code.You might have to run a static analysis first to note the base shear and then run a response spectrum if code requires. ETABS has checks built in to make sure it uses the corrects time period. You can print the summary sheet to see that ETABS makes sure the limits sets by code are followed. Thanks.

You can have a look at some existing ideas discussed in the forum: https://www.sepakistan.com/search/?q=fyp Thanks.

Welcome to the forum Bilal. Its always great to have people with site experience here.

Welcome to the forum. Glad to have you.

Hi Hamad, It is good that you have posted here. Here are my thoughts: Generally for jobs, the start point would be connecting/ networking with your friends from Bachelors Degree as most/ all of them would be employed and it would be easier for them to get you in their firms as they know you personally and can vouch for you. There are companies in Pakistan that do work specifically on post-tensioning like Izhar or other Bridge Construction Companies. I would suggest getting back to your friends first and if that doesn't work, scan through advertisements in newspaper. You can also connect with people here that are active to see if they have an opening in their office etc. Thanks.

Hi Tufail, Source: https://www.amazon.ca/Concepts-Applications-Finite-Element-Analysis/dp/0471356050 This book is taught in most universities in Pakistan (NUST does it). You can contact someone who is doing masters and he would be able to lend you a copy. Thanks.

HI Tufail, Those locations are called Frame Output Stations. You can modify them in ETABS by: Source: http://docs.csiamerica.com/help-files/csibridge/Advanced_tab/Assign/Frame/Frame_Output_Stations.htm Thanks.

Yes it does. For meshing it is extremely important to have regular elements and divide it in such an way so all your mesh nodes line up. I know ETABS has a feature called Auto Edge Constraints, which allows you to not worry about it. But, what I would recommend is not to use Auto Edge Constraints and do a manual mesh where the nodes line up. Your model will be free of error then. Also, another important thing to keep in mind would be making sure your boundary conditions (the supports) are assigned correctly so that model is not unstable. Here is the definition of Auto Edge Constraints feature: I am not sure about strips in ETABS but you can use Section Cuts to get required forces at any location. Update your model and let me know. Thanks.

Maleeha, Here is a description of the option: Source: http://docs.csiamerica.com/help-files/sap/Menus/Define/Section_Properties/Frame_Sections/Reinforcement_Data_Form.htm Thanks.

Thanks for sharing.

MIK, Here are some relevant discussions that you might be interested in about load combinations, special seismic term and omega etc that you may find useful:

For the image shown above, the only other thing that I can think of is that your aggregate size should be small enough so that concrete can easily flow between the two rebar layers. Thanks.

You can provide a big pedestal that can support the tank and have a raft below. If the tank is supported on steel skirt (circular steel vertical ring) this is mostly the case for vessels, then you should apply the load as line load. If that is not the case and the tank is a simple tank (flat bottom), then just provide cementitious non-shrink grout between your pedestal and underside of tank and apply the load as UDL on the pedestal. Let me know if you have any additional questions as work in Petrochemical Industry and this is very common. Thanks.

You can also see the following topics on Building Drift to get some idea about what the code says about drift and other important things to keep in mind. Thanks.

I am not sure about the exact number recommended by National Environmental Quality Standards but here is what I found: Thanks.

Generally speaking, newer versions come loaded with new features so if you aren't using the latest and greatest, you are missing out on a number of newly added options. I generally recommend the version for which you have read the Software Manual. It is very important to know the limitations of your ETABS/ Structural Engineering Software version. Nothing else matters as much as that. Thanks.

Hi Luk, What is the question about the cantilever? Can you please explain so people that don't have access to ETABS but would like to comment on it can do. Thanks.