UmarMakhzumi

Uzair,
 
My plan is first publish a number of articles under SEFP consistent design. This is important for a number of reasons. The most relevant reason related to subject thread is that It will also help me identify who is willing to take time out and do some research, put it in your own words and tweak it as per the practice in Pakistan. I am willing to proof read all the articles.  Once I can find enough members like these, we can set up a Committee and do what you are recommending.
 
I have got the following topics that interested members can start working at:
 
Confined Masonry: Building Safer Houses
 
Long Term Deflection of Concrete Beams
 
Concrete/ Steel Pile Design
 
Stability and Strength: Fundamentals and Basics 
 
Seismic Design: Cord and Collectors
 
Dynamics Design: Fundamental period, frequency and mode shapes
 
Members are more than welcome to suggest something they want to write. Please don't put your final year project thesis here. The articles that we plan to publish are meant to be different.
 
Thanks.
 
 
 
 
 

Assalam O Alykum Muhammad 
ASCE 7-02 Chp 9 
 

I will agree with above and suggest you try to look for something in the UK market as this will be hugely beneficial for you professionally and the experience will be immense. the projects and there nature is different in UK market and u will be surprised with the approach methods for each design problem. This will provide you a good base and will help. I am sure you will land a job soon but keep your focus there only. 

I would suggest that you network in UK and try to get in some company there instead of looking at Pakistan.
I know some friends who went abroad and were able to land something based on their networking skills. Your starting point is your University Alumni Network. Good luck.

*SEFP Consistent Design*
*UBC Seismic Drift Limits*
*Doc No: 10-00-CD-0003*
*Date: June 04, 2013*
 
The goal of this tutorial is to demonstrate how to evaluate building drifts and story drifts using UBC 97 guidelines. The philosophy behind Story Drift Limits is “Deflection Control”; In UBC 97, deflection control is specified in terms of the story drift as a limit on the lateral displacement of one level relative to the level below. The story drift is determined from the maximum inelastic response, ΔM.
 
Let’s start by defining the design-level response displacements. The elastic deflections due to strength-level design seismic forces are called design-level response displacements. These are denoted by ΔS, where the subscript ‘s’ stands for strength design. Design level response displacements are what you get out of your software, when you run analysis. Please note that structural analysis softwares may provide these values in different formats; say a percentage of height or a direct output.
 
Well, to calculate your story drifts, first you need to find maximum inelastic response displacements from your design-level response displacements. The maximum inelastic response displacement is defined as:
ΔM = 0.7RΔS
Where, R is the structural system coefficient, the subscript ‘m’ in ΔM signifies that we are calculating a maximum value for the deflection due to seismic response that includes inelastic behavior.
 
Seismic drift values are much larger than wind values. UBC uses maximum inelastic response displacements rather than the design level displacements to verify the performance of the building. Seismic drift limits are 2% & 2.5% of the story height for long and short -period buildings. For a floor to floor height of 12 feet the max., allowable inelastic drift value would be 2% of 12 feet= 0.02*12*12 in=2.88 in. For wind for a 12 story height, drift would be L/400=12*12/400 =0.36 inches, A comparison of both wind and seismic drift limits shows that earthquake inelastic displacements are quiet large compared to wind displacements. That is why proper detailing is emphasized in seismic design.
 
When calculating ΔS for seismic, make sure:
You have included accidental torsion in your analysis. Use strength design load combinations: 1.2D + 1.0E + 0.5L & 0.9D + 1.0E. You are using cracked section properties for reinforced concrete buildings. Typical values are Icr walls= 0.5EcIg, Beams = 0.5EcI g & for Columns 0.5 - 0.7 EcIg. Use a reliability/ redundancy factor= 1 to calculate seismic forces. Whenever the dynamic analysis procedure of §1631 is used, story drift should be determined as the modal combination of the story drift for each mode. Determination of story drift from the difference of the combined mode displacements may produce erroneous results because maximum displacement at a given level may not occur simultaneously with those of the level above or below. Differences in the combined mode displacements can be less than the combined mode story drift.  
Example:
A four-story special moment-resisting frame (SMRF) building has the following design level response displacements.(See attached Image)

R= 7.0,
I= 1
Time period= 0.6 sec
(See the attached image for Story Information)
 
 
Calculate:
Maximum Inelastic response displacements. Story drift in story 3 due to ΔM. Check story 3 for story drift limit. Maximum Inelastic response displacements ΔM = 0.7RΔS
ΔM = (0.7) (7) ΔS = (4.9) ΔS
(See the attached image for Maximum Inelastic response displacements)

 
Story drift in story 3 due to ΔM Story 3 is located between Levels 2 and 3. Thus
ΔM drift = 5.39 - 3.43 = 1.96 in.
 
Check story 3 for story drift limit. For structures with a fundamental period less than 0.7 seconds, §1630.10.2 requires that the ΔM story drift not exceed 0.025 times the story height. For story 3:
Story drift using ΔM = 1.96 in.
Story drift limit = 0.025 *(12*12) in = 3.6 in. > 1.96 in. Therefore, Okay.

So looks like today, I came across the same problem that is being discussed here. I had to provide a design criteria for a buried concrete pit. I will summarize my findings below for the benefit of everyone. This applies to structural members that are subjected to environmental exposure conditions or that are required to be liquid tight. 
1) The first step is to calculate flexural demand in the walls of concrete pit/ water tank based on all possible conditions. For the case of buried concrete pit, it included, empty condition (no fluid in the pit) , operating condition (full of liquid), test condition (no backfill  around the pit and it is full of liquid) etc. Buoyancy checks should also be performed.
2) Compare required flexural reinforcement against minimum reinforcement ratio = 0.006 per ACI 350, Table 7.12.2.1 & ACI 224 , Section 3.5 and provide whichever is the maximum. The ratios provided are basically temperature and shrinkage reinforcement ratios based on gross section so provide half of the reinforcement at each face.
3) Satisfy maximum crack width of water-retaining structure = 0.10 mm, ACI 224R-01 Table 4.1 based on the reinforcement already provided. If the reinforcement is inadequate, increase the reinforcement till this requirement is met. To meet this requirement, smaller bars should be used with close spacing.
Now a few comments on the the excellent discussion above.
@Khawaja Talha post above is applicable for all normal cases where there is a restraint to shrinkage and temperature movements only. If you have a condition like that, you need to provide 0.45% reinforcement ratio in your slabs. Example of a situation where this would be applicable will be a structure where movement or expansion joints haven't been provided at industry standard spacing. But if you want to meet liquid tight start with 0.6% as a minimum and work your way as suggested above.
Other posts above explain the same things in a slightly different manner but all good.
Thank you
 

As explained above that metal deck have inbulit shear capacity for the shear flow in some cases and if the joists or beams below are designed for the simply supported cases than the metal deck is pretty much behaving like a scaffold. So it is possible but again check your design requirements and if they are complied than should be no issue. 

How did you come to the conclusion that you need 21" thick slab for one way slab of 26 ft span?
Anyone who is not familiar with the project, is not in good position to recommend you to go for two way floor system. Architectural constraints can control. Check seismic demand, and the related ductility demand; the seismic considerations may govern as well.

These equations are not not meant for one-way floor system. You should know it.

What is the basis for this?
Why E is not divided by 2.5 or 3? 
Masonry has no to limited, out of plate strength. How are you making sure, your modelling approach is different from modelling a shear wall..?
 

All the loads occur on the ground slab will distribute on the soil. No need to model the ground slab. Take care Don't forget to add subbase material underneath the slab on grade. Also take the storage rack loads from the supplier.
However, in case you are going for traditional slab on grade you need to provide proper joints around the pedestals and Isolated joints around the ground beams , retaining walls etc. and special care is required for the joints spacing as per the ACI code. refer to clause attached. Generally contractors cannot achieve the required tolerances for the traditional slab on slab. for example FM2 , FM2 specialist etc as per technical edition TR-34 if required by the suppliers.
In addition, warehouse ground slab can also be go for the jointless slab designed by specialists like Twintec or Hak which is more cost effective. Profilo graph floor profile method can be suggest for VNA racking type if exist to verify the required tolerances. 

Spot check is required

Sundass,
The first thing will be to confirm if the loads are applied correctly and modelling is done correctly. That can be confirmed on your end.
For loads, should first see which load combination is governing. Say 0.9*D + 1.5Live is governing. You can manually calculate the dead load, and the live load. Check the reactions of basic load case of live and dead to your manual numbers to see if they match.
Once you have done it then comes the modelling. For modelling, the easiest thing would be to confirm deformed shape for each load case in the governing load combination and observing if it makes sense. Another thing that you can do is to use a spreadsheet or manual calc for column design or another software like PCA Col and check ETABS results.
It could be, be it requires checking and making sure there are no mistakes. Basic checking is required.
 

Waqar,
You can change your column framing by adding more columns so load on edge columns is smaller than what you have now. Also review your load input and sharpen the pencil to see if there is any conservatism in the loads and take them out.
Thanks.
 

I have done some search in my content dump, and I found ground snow values(kN/m^2) as well as wind speed values(m/s) based on IBC 2006, International Building Supplement. The values are for Karachi, Islamabad, Peshawar and Lahore only.
 
Here are the two pre-notes that go with the attached tables:
 
 
Here are the two foot-notes that go with the attached tables:
 
Now regarding design values for places like Murree or Northern Pakistan, which receives biggest chunk of snowfall, my personal recommendation would be to use values for Fort McMurry, Alberta, Canada. You can use this link(http://www.jabacus.com/engineering/load/snowload.php) to quickly calculate snow load for Fort McMurry or any city in Canada.
 
To establish a baseline, you can do a comparison of average annual snowfall for Fort McMurry(or whatever city you selected: Edmonton, Saskatoon and Regina would be some good choices in addition to Fort McMurry) to the area that you are designing to get a feel for how conservative your number are.
 
You may have to some search on google for Pakistani Cities average snowfall data but it would be worth it. Do share it here if you come across any.
 
This sums up my 2 cents.
 
Thanks.
 

Thanks @Ayesha for your prompt reply.
According to ACI-318-19 section 22.9 
 
This section is also applicable to construction joints, as highlighted in the above snaps from ACI-318-19. I was asking about Avf in the above equation 22.9.4.2 which is the area of reinforcement crossing the assumed shear plan (in our case interface between old and new concrete). Provided flexural reinforcement is raft is also perpendicular to the assumed shear plane (interface between two concrete pours)
The same problem is discussed in the link below
https://www.eng-tips.com/viewthread.cfm?qid=477681

You can use the recommendations in the paper that allow use of axial compression and rebar perpendicular to crack surface to be accounted.  If I were you, I would just use the conventional method described in the paper and ignore any contribution due to rebar (see snapshot for the method/ equation). 
 Also, I have difference of opinion for your case. I checked the topic at Eng-Tips as the question is explained in much More detail than here (I would suggest you edit your question above and include additional details). The location you have chosen is under compression as directly under columns. You shouldn’t be worried about shear or moment there. 

The paper is the one you referred in Eng-Tips.  
Title: SHEAR TRANSFER IN REINFORCED CONCRETE - RECENT RESEARCH
Date: March-April, 1972
Volume: 17
Issue: 2
Page number: 55-75
Author(s): Alan H. Mattock, Neil M. Hawkins
Download Link:
https://www.pci.org/PCI_Docs/Publications/PCI Journal/1972/March-1972/Shear Transfer in Reinforced Concrete - Recent Research.pdf
You can see page 61 of the PDF to see the definition of items in the equation. Another alternate would be to provide epoxy grout to join the two surfaces on either side of the crack. In that way no calculation is required.
 

Of course you can with epoxy grout as bond strength is even high than compressive strength of concrete for most epoxy grouts. You have to check the data sheet. The important thing would be surface prep as aggregate would need to be exposed to half depth and extremely good cleaning. Once you have used epoxy, there is no construction joint at that location. Just remember that.

Yes as it is more conservative.

Without shear studs, horizontal shear can not transfer between RC slab and metal and there is no composite action between metal deck and RC slab .
Some manufacturers of metal deck have designed their product such that their decks develops some degree of composite action without shear studs. Depending on the design loads, that may be enough.
Check your design loads and related effects to decide if you need 100% composite action.

Salam Everyone!
 
We are a steadily growing community now. I thought about posting forum rules which are always a good idea to keep new members streamlined to forum decorum. Please do share your thoughts on any modifications to the rules. 
Read the forums rules and guidelines before posting for the first time. Please use first names to address people & don't address anyone with a prefix. Calling someone Sir is prohibited.  Search the other posts to see if your topic is already covered. Use a meaningful title for your thread and topic tag. Do not use a forum to promote your product, service or business. Be civil. Personal differences should be handled through email or IM and not through posts displayed to everyone. Stay on topic. Ignore spammers, respond to them personally and not through the board, or report them. Use plain text over HTML if you want your post to be readable by everyone. In order to be understood by most people, use correct spelling, grammar and avoid slang unless you know the word or phrase will be understood by other members. Do not double post (post the same message twice in one thread) or cross post (place the same message across several forums). Act in a give and take manner; help others as often as or more than you ask for help. Do not use all caps or SHOUT in your posts. In addition, one exclamation point is enough. When replying to a post, do not quote more from the previous post than you have to. Do not post new problems on someone else's thread and interrupt a topic of discussion. Do not use someone else’s thread for a private conversation. SEFP prohibits warez, cracks or illegal downloading of software and similar topics. Watch your sense of humor, posts may be read by people from a variety of backgrounds and ages. Do not use a huge and annoying signature, a modest signature is fine, moderators may remove large ones anyway. Do not post any information that you want private. Posts should not contain personal, identifiable information or content embarrassing to others. Do not post content that violates a copyright. Do not post ”empty” or useless responses, such as just ”lol” or ”cool.” Only post responses when you have something to contribute. Write concisely and do not ramble. Do not use words like ”urgent” or ”important” in your subject line, be patient. Post stuff on the forum rather than sharing through other means(email etc). If your desired attachment type is not supported, inform the moderators so that changes to board can be made. You can always zip files and upload them. Do not chastise newbies.

Saugat,
Static base shear is based on first mode so it is kind of conservative.
Thanks,

This doesn’t look right and beam for sure looks under-reinforced. If you have done the calculation, you can share and see if someone has time to review here.
 
If you don’t have structural engineering background, contact a structural engineer, pay him and get this designed.
 

Normally analysis for such cases is better suited considering Abaqus or other FEA softwares that can allow you to model the interface between CFRP and existing material. Frame analysis can be done by defining custom properties for locations where such reinforcement is used and then you can use the forces at that location to analyze the location in Abaqus or any other FEA software for limit state that you are interested in.