UmarMakhzumi

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Attached are two docs I got from Google; they are lucid and easy to understand and cover examples. Pile Groups (Literature).pdf, Pile_Foundation_Design.pdf With Dynamic loading, the question is not about piles designing only, but in fact, you need to design a foundation system and satisfy vibration limits for the machine. I can share with you typical rule of thumbs for dynamic design of machine foundations. Keep me posted on this as this is my specialty in structures. 1) Your utilization for piles should not exceed 45 - 55 % of capacity under static loading. This is to ensure that soil remains fairly elastic and expected behavior is achieved. 2) Is the boiler centrifugal or reciprocating machine ? You can check ACI - 351 that talks about minimum ratios of foundation weights to machine operating and their CG Locations for both centrifugal and reciprocating machines. 3) Your center of resistance for pile group should be with in 6-7% of machine C.G. 4) What is the max vibration limit for the boiler on the foundation level and at the machine CG level ? You normally get this information from the vendor and you proportion your foundation to satisfy those limits. 5) I am interested in knowing that how would you do a dynamic analysis for the system ? 6) You need to have complete soil investigation report with SCPT test providing shear wave velocities in each soil layer. 7) Is the foundation system an elevated one or is at ground level ? It is important to know this as table top machine design needs more engineering input and caution ? 8) What is your acceptable Human Perception Limit for the system ? 9) Is the foundation system being shared by super structure too. Please provide foundation plan. I want to see what is around your boiler. 10) You response of foundation should be outside the operating range of the machine to avoid resonance. (V.Imp) 11) Please reply asap . Thanks.

What kind of machine is that ? Would the operation of machine induce any dynamic forces in the foundation ? If yes, then pile design is a total different story. The static design of pile is easy. Depending upon what kind of pile you select (friction, end bearing) Consider your pile cap as rigid plate and find reactions at pile locations and design. Thanks.

Design beams manually.

The concept is that: "Shoot for the moon, even if you miss, you will land in stars". Just because you are trying to achieve something that is not possible from one perspective and even if you don't achieve it you will still become something not as great as your inspiration but better than what you used to be.

There is no such thing as being realistic. Everything is possible. Be ambitious. Challenge everything. Success is continuous failure and that is what defines a successful person. Just go and happen to things. Allah will help you.

Good One Rana.. I will go through them to see if I have any suggestions for you. Keep up the good work.

Welcome Aboard!

I have done some NDT Projects with Arif Consulting Engineers. Here is the website with all the contact information. http://www.aceconsults.com/

Naeem, your model is incomplete. There are no load cases defined other than dead. Wind will govern the design for the structure. You members are almost all overstressed in basic gravity load combinations. Your should provide complete braces to the foundation so that for all lateral loads (esp wind) load path is complete and there is no bending in the framing members. I should have seen this way before but I am sorry due some unexpected work I couldnt check it. Anyhow, revise your framing. Put cross-braces or chevron bracing on all faces instead of knee braces; that will make your forces from top to bottom through tension and compression and you dont need any moment joints. Apply wind load (v.v. imp) . if you dont know how to do it let me know. I can help you for auto loading in SAP. Your model needs a lot of rework.

I did a blast calc when I was in Pakistan for an embassy. Check the attached files. The other references that I have but cannot attach because of their substantial size are: Dynamic Loading and Design Of Structures-AJ Kappos Thomas Telford - Blast Effect on Buildings ASCE - Design Of Blast Resistant Petrochemical Buildings I got all this stuff from google searches, so would be easy to find it.(I can always email you the stuff let me know if needed) Thanks. Blast Barrier Design and Testing.pdf

I have started looking at it. Hopefully will be done by this weekend.

I will check your RISA Model and get back to you on this. Do you have any further details about the working of chair lift system as Syed asked ? Thanks

There is one by Collins And Mitchelles on Pre-Stressed Structures. It is also very good.

Thanks for sharing the drawing in pdf format. I am writing down a design approach, and would request everyone to throw their comments and questions. Lets start by: 1) Design Criteria 2) Expected loads on structure 3) Possible limit states 1) Design Criteria I believe that you have been working on this for some time and will be having a design criteria outlining what code do you want to design this structure on, and what material strengths do you intend to use. Please post the design criteria document here. 2) Expected loads on structure The structure is a pair of columns, with motors installed at the top of the that push/ move the chair lift. I would recommend that each column pair would be joined and braced at different levels to provide a stiff support (how far are they ? ; present framing doesn't look to work, I would suggest a truss tower). Possible loads are: Weight of motors. Possible thrusts at starting and stopping of chair lifts or when faced with load shedding. Weight of chair lifts and passengers (considering number of persons and chair lifts at a given time). Wind load on columns. Weight of cable and its reaction on columns. (Cable are eccentric from column center) 3) Possible limit states Apparently, columns need to be laterally stiff enough to maintain tension in the chair lift cables. Uneven support settlement. Utilization of piles to be kept to 60% and under to avoid that. It also depends upon various factors, but I am just throwing in a bullet. Maximum unsupported length of cable. You many wanna do a check on that to make sure things outside your scope don't fail. I remember, we did a problem in Theory of structures for a suspension bridge. Similar concept. Overturning Check. Shear failure of piles. (throwing in a bullet) Anchor Bolt Failure. (from sketch it looks like anchor bolt shown are typical and not designed) Frost Jacking. You can use a higher importance factor as failure can be catastrophic. Some other questions. How good is the geo-technical data ? Please share: what you have done till now. Also list things that you haven't designed and are using typical details. Are anchor bolts designed ? Are piles designed properly ? How are you calculating wind load ? what code ? are you doing any manual checks on that or just software ? What is the seismic class of the site ? Are there any structures near by ? How high is the water table ? What is the confidence level on structural steel available ? Local from a mill or properly tested sections. Is the soil subjected to frost heave ? Are piles and pile cap designed for that ? Are piles concrete or steel ? Do you have more drawings to share ? You foundation looks inadequate ? Free standing columns(present framing) would be out of proportion. I would Suggest having a Truss Tower; load path would be robust and your site construction would be easy and cheap too. I would welcome comments and more questions. Naeem, I am looking forward to your reply. Cheers.

The best classic on the subject (not specifically membranes) is Theory of Plates and Shells . You can download it free from here. Since, this is a university course, I would recommend you to stick to your reference books more. Thanks.

5% of building dimesnion perendicular to the direction of seismic load is default. However, code requires engineers to check to trosional irregularity, which if found requires the default eccentricity (5%) to be increased.

Cant open the archive. Can you please upload drawings as pdf? Thanks.

No idea about Pakistan but OHSA is highly valued in Canada. You can be an HSE Engineer and they mostly call shots on design related issues where saftey is a concern. From my memory, I can recall that there is a construction firm in Islamabad called "Kestral" where I came across an HSE Engineer(so companies who hire HSE Engineers would value this course). It is very likely that OHSA related jobs are in good number in Middle East.

I haven't done something ditto to what you are explaining, but I would like future information on this being shared, so that, may be, we can develop something ? Thanks.

Here is the discussion. http://www.sepakistan.com/topic/1307-etabs-load-combinations/ Thanks.

Can you please share the drawings? Thanks

Ramadan Mubarak Everyone! Hope you all have an excellent one.

Delete columns at the end of your shear walls and your results would become even. Check your building for torsion irregularity and drifts. You cannot always have a symmetric framing.

Check the attached snapshot!