Jump to content
  • Welcome to SEFP!

    Welcome!

    Welcome to our community forums, full of great discussions about Structural Engineering. Please register to become a part of our thriving group or login if you are already registered.

Recommended Posts

Hello Everyone,

I would like to draw your attention to questions being asked in message boxes instead of being posted on forum. The reason I am raising this is that recently I have seen a spike of inbox messages addressed to me asking for solutions rather than the question being posted on the forum. I assume others are getting similar messages. FYI, I don't have access to inboxes and all your conversations are 100% private. I would like to request everyone to please ask questions on the forum and discuss it on the forum instead of inboxes. The reason being that the discussion can be beneficial for the rest of the community and also other members can then critique or appreciate an opinion.

Let me know should you have any questions.

Thanks.

Share this post


Link to post
Share on other sites
14 hours ago, UmarMakhzumi said:

I would like to request everyone to please ask questions on the forum and discuss it on the forum instead of inboxes. The reason being that the discussion can be beneficial for the rest of the community and also other members can then critique or appreciate an opinion.

Very important message!

I myself have received questions in my inbox more than once, from some of the forum members asking for help on various technical matters. However, I have always advised them to put the questions on the forum, as it has multiple advantages, both for the originator as well as for rest of the forum members.

By posting the question on the forum (instead of sending to an inbox),  the problem is visible to all the members, and it is likely to get not only a quicker response but more & better responses as well.

In addition, the question and responses are helpful for rest of the forum members in general, and those members particularly who do have same problems but somehow (due to shyness etc) couldn't ask the same questions on the forum themselves.

In view of the above discussion, I strongly second the opinion of UmarMakhzumi, for posting of problems to the forum itself, instead of sending them to inboxes of moderators or other forum members.

Regards.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Our picks

    • I am suppose to design a pile foundation for a machine weighing approximately 50 tons and with an operational loading of 100 tons. 
      I ll appreciate your help in terms of guidance & provision of notes...  
       
      Thank you..
      • 36 replies
    • Material behavior can be idealized as consisting of an 'elastic' domain and a 'plastic' domain. For almost 200 years, structural design has been
      based on an elastic theory which assumes that structures display a linear response throughout their loading history, ignoring the post-yielding
      stage of behavior. Current design practice for reinforced concrete structures is a curious blend of elastic analysis to compute forces and moments, plasticity theory to proportion cross-sections for the moment and axial, load, and empirical mumbo-jumbo to proportion members for shear.

       

      From the book "Design of Concrete Structures with Stress Fields" by A. Muttoni,  J. Schwartz and  B.Thurliman.

       
      • 0 replies
    • Dear Fellow Researchers, Academicians, and research students,

       

      NED University of Engineering & Technology in collaboration with Institution of Engineers Pakistan (IEP) is organizing 9th International Civil Engineering Conference (ICEC 2017) on December 22-23, 2017 at Karachi, Pakistan.

       The congress details are available at its website www.neduet.edu.pk/icec

       Also attached is congress flyer for information and dissemination among your peers.

       Abstracts submission deadline has been extended till October 31, 2017.

      Please click on the link to see the full description.
      • 0 replies
    • AoA all,

      Is it mandatory to do column concreting upto the soffit of the beam in a single pour ?

      What code says about the construction/cold joint location in column ?

      Majority of the contractors are pouring the column concrete upto the soffit of the beam (full height of the column), some contractors leave the column height about 9" to 12" below the beam level and then fill this 9" to 12" column height with the beams & slab concreting. On one site column concreting was stopped at the mid height and the remaining half was filled on the next day.

      Thanks

       

       
      • 5 replies
    • AOA 

      i am facing problems in shear wall design .what are the pier and spandral ?what will be the difference when we assign pier or spandral? without assigning these the shear wall design is incomplete .

      i am taking about etabsv16

      someone have document about shear wall design plz provide it 

      thank you

       
      • 9 replies
    • Salam Members,

      Congratulations to Engineers, PEC has become full signatory of Washington Accord, what are the benefits to Pakistani engineers for this agreement. 

       

      Regards   

       

       
      • 3 replies
    • Please clarify the following confusions one by one:-

       

      1. If we run P-delta analysis in ETABS, then should we ignore stiffness property modifiers for beams and columns? I have heard that if we perform P-delta analysis and apply stiffness modifiers at the same time then the moment magnification process is doubled...?

       

      2. ETABS considers selenderness of a column by applying moment magnification factors. If we run P-delta analysis also, does it mean that the selenderness of column is being over-estimated? I mean once the moments are magnified in P-delta analysis process and again through moment magnification process?

       

      Please help me understand the software myth and clarify above confusions.
      • 1 reply
    • Assalam o alaikum.
      According to ACI 12.5.2,
      development length for fc' = 3000, fy=60000, for normal weight concrete and epoxy less reinforcement, The required development length comes out to be
      for #3 = 8.2 inch
      for #4 = 10.95 inch
      for #6 = 16.42 inch
      for #8 = 21.9 inch
       
      And if in my case, ACI 12.5.3 is not fulfilled, it means now i have to provide ldh as mentioned above. ldh is STRAIGHT EMBEDMENT LENGTH + RADIUS OF BEND + ONE BAR DIAMETER as shown in figure attached. Now my question is, if in my case, main reinforcement of beam is of #6 and #4, minimum column size required will be 18 inch and 12 inch respectively. Lets say by any means, i can not select #4, #3 bars and size of column where bars are to be terminated is 12 inch, how to fullfil this development length???
      • 11 replies
    • Dear all,

      I am trying to design shearwalls through ETABS with temperature load applied over shell. At various location, spandral section fails in Shear due to temperature and piers (sometime in shear, mostly in flexure).  (See Attached Image)

      Certainly all the problem in Shearwalls are due to temperature. I don't want to increase cross section of spandral or pier at some location just due to temperature load case as it will appears non-uniform with rest of the wall. 

      I have seen stiffness modifier affect distribution of forces and also rigid/semi rigid daiphragm assumption. 

       

      Can anybody guide how to properly design the shear wall with temperature load applied in ETABS or share any similar experience. Thanks in Advance.    
      • 15 replies
    • ENGINEERS;
      I WILL LOOSE MY BRAIN FROM ETABS. 
      I DECIDED TO MAKE MANUAL MESHING FROM AREA ELEMENTS BESIDE EACH OTHER AND EVERY HING WAS FINE .
      BUT AFTER DEVISION SAY 7*7 ELEMNTS FOR EVERY BIG ELEMENT AND MAKING ETABS CHECH..................THEN 500 ERROR MESSAGE THAT ALL ELEMNTS ARE CLOSE TO EACH OTHER.  WHAT ARE GOING...... SOMEONE TELL ME PLEASE...... I WILL LOST MY WORK
      • 6 replies
  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By miqureshi77
      Dear Developers of SE PAKISTAN, 
      I would like to congrats you for making this useful website and thanks for your efforts and dedication for continues working on this site.
      As technology grows and people's are more handy to run android apps.
      So I would like to request you to launch android app for this website
    • By UmarMakhzumi
      Dear All,
      The forum has been recently upgraded with tons of new features. Please take a minute and explore the new items. Your feedback is much appreciated. You can check out the following thread that summarizes biggest changes to forum. 
      Thanks.
       
       
    • By UmarMakhzumi
      Dear All,
      I have just finished modifying a bunch of stuff related to member roles and I am very excited to announce it.
      There are some new member roles that have been created:
      1) SEFP Associate
      As you know that I have been requesting help with a number of stuff on SEFP and there are very generous people who have volunteered. To recognize their effort, I have created this role. An example is @Saad Pervez, who is doing an excellent job running our Social Media pages. From now onwards, you will find him assigned to SEFP Associates. Thanks Saad for your help.
      2) SEFP Contributor
      There are a few members who have been with us through thick and thin. Because, they have regularly answered questions and contributed to forum by not only providing information but their engineering judgement, this role has been created in recognition of their efforts.  @Ayesha has been assigned to this and we look forward to add more members to their club.
      3) SEFP VIP
      @EngrUzair deserves this without any question. He is the most senior member of the forum providing invaluable support. Not only this but he has also been a teacher at our beloved Alma Mater. I have created this category in recognition to his efforts.  We "might" be adding very few people to this role in upcoming years.
      4) Moderators and Super Moderators
      Our current staff consists of @waqar saleem, @Rana and @BAZ. @Rana and @BAZ have global moderation over the forum and @waqar saleem is currently moderating all the technical sections. They all are doing a great job and I am very thankful them. Because of overall moderation assignment, I have split moderators in Super Moderator and Moderators. Supermods might also get portion of Admin rights over coming years. I have a plan for that but nothing set in stone.
      Like always, please provide your feedback and let me know what else should be done/ undone.
      Thanks.
    • By UmarMakhzumi
      All,
      Starting today, I would be experimenting with some advertisement options on the forum. That would include making ads visible to guests (non-registered members) only. It would also help me estimate the amount this site can pay for itself. Right now, the estimated projections are very low in-terms of revenue (5-10% max of yearly budget). Members would always see a clean forum (no ads).  Guests, however would be subjected to Ads.
      Any suggestions or ideas are welcome.
      Thanks.
       
    • By UmarMakhzumi
      Hello Everyone,
      Here is a list of new features in the upcoming update:
      Updates to Editor ( @EngrUzair might like this one )
      Fluid Forum View ( @Rana check this out)
      Reactions
      Recommended Replies (Moderator Related Stuff)
      Content Messages (Moderator Related Stuff)
      Leaderboard Enhancement
      Richer Embeds
      Forcing Members to Complete Profile
      Improvements to Social Sign In
      Clubs  (Clubs will allow forum members to create their own groups in the forum and discuss things other than structural engineering)
      I am very excited about all these improvements. Stay tuned for more. This update is expected to roll out in summer.
      Thanks.
    • By UmarMakhzumi
      All,
      You can now get a free email @sepakistan.com. All you need to have is more than 25 posts (Title of Lieutenant).
      The email is a forwarding email, meaning that you get to keep your original email and all emails sent at your email@sepakistan.com will show up in your original email inbox. 
      Let me know if anyone is interested.
      Thanks.
    • By UmarMakhzumi
      Hello Everyone,
      If you ever wanted to contribute towards SEFP, here is your chance. We at SEFP need help with the following:
      1) 2 volunteers to help us run our Facebook page. If you don't mind taking 10 minutes out each day to share a few articles from this website to the Facebook page, then this position is for you.
      2) SEFP Mentoring Circle Coordinator is required. We are planning to start Mentoring Circle and would need someone to be the co-ordinator of the program. 
      If you are interested, please let me or any other moderators know.
      Thanks.
    • By Rana
      I think its time now to categorize questions based on the difficulty level.
      For example;
      A toddler asking very basic question like what is mass source or time period, should be classified under lets say Easy or 0 or Beginner or Simple etc category. And as such specific moderators should be assigned to take care of that forum.
      Then we can make other sections like moderate or difficult. Where one really need to relearn/review the question and think about the answer carefully.
      I think all the internet is full of the same basic questions like time period, base shear etc. Isnt it the time to take SEFP a step ahead and not just another forum full of the same basic questions? How can we re-categorize the SEFP sections to give it a new feel, not just like concrete, steel, software issues etc. What do you think?
    • By UmarMakhzumi
      Dear All,
      Please see the latest member rank hierarchy that has been implemented. Your feedback is more than welcome.
      Thanks.

    • By waqar saleem
      Dear Friends
      i would like to suggest that if we make city based SEFP chapters for more frequent interactive meetings. What are your suggestions? @admin. subject to admin approval.
       
      Regards
       
  • Recent Discussions

  • Latest Forum and Club Posts

    • 1. First of all, you need to understand how to design the slab on grade (SOG) through hand calculations. Later on, you may develop a spreadsheet or use some patent software to do it using a computer. 2. The references given above provide design methods (pca, WRI, COE etc), dealing with different types of SOG (e.g., unreinforced, reinforced concrete, post-tensioned etc.) subjected to various types of loads (uniform, line, wheel & post loads).  3. Before starting the design, you will need to go through the reference available with you (i.e., ACI 360), and a. Select the SOG type from the Section 7 onwards, applicable to your case. b. Study the design requirements from the relevant section c. Determine the type and intensity of various loads, the slab will be subjected to during service. d. Solve the relevant design examples, given in the appendices of ACI 360 to understand various design parameters, charts, equations & their application to the design. e. Using the design prameters applicable to your slab, design the SOG by following the procedure adopted in the reference design example. HTH Regards.
    • thanks sir, would you please to tell me how to put the load? i've modeling the slab in SAFE then i assign the area spring, and put the surface load, due to uniform load and i get 0 moment i think i'm wrong in assign the load, i wonder if someone would explain it how to analyse slab on grade using SAFE, i've read the ACI 360, but still not to understand. Thanks
    • I have not seen such a limit written anywhere. However, the lowest value of bearing capacity (BC) for the building sites I have come across during my professional practice, was mostly 0.5 tons per square foot (TSF). In only one case, the reported BC was 0.25 TSF. However, the client was advised to change the site, as such a low BC indicates a very weak soil, ordinarily requiring a very heavy & expensive footing design. As such, IMO 0.5 TSF may be considered a reasonable lower limit of BC for a building site. Regards.
    • You may use following sources for designing floor slabs resting on ground:- a. Designing Floor Slabs on Grade by Ringo & Anderson, 1996 ( Link ) b. ACI 360R-10 Guide to Design of Slabs-on-Ground Regards.
    • anyone please advice how to design slab rest on grade? anyone have a referen? i have analyse with SAFE, but i still not confirm with the value of k (subgrade modulus) and the load. that the load assign full on the slab or just partial load at the critical location? thanks
    • 2d analysis is never recommended with walls above. https://wiki.csiamerica.com/m/view-rendered-page.action?spaceKey=safe&title=Modeling+uplift+and+foundations+on+soil+supports  
    • Hey man, hold on. Your building isnt symmetrical. Also the theres difference between axial stiffness of cols vs walls. This will effect z direction deflections from bottom to top stories. 2nd thing..safe..in safe deflections will be different than in etabs. This has been discussed no of times here and you can search.
    • If I calculated for an example the total area of rebars in a beam and I got let's say 433 mm2 I can now choose let's say 4 - 12 diameter bars or 2 - 16 diameter bars in a 300 mm width beam both will satisfy the minimum reinforcement and the maximum and minimum spacing due to ACI code. Does it matter if I chose any of them ? I know that the lesser the spacing between rebars the better to resist internal cracks in concrete. What are your thoughts ?
    • Does code recommends any minimum limit for bearing capacity if the bearing capacity of actual soil is known?
    • Hey guys, I think I have found what's wrong but don't know how to fix it.

      I drew the slab on SAFE and I have obtained the beams moments and slab deflections and they were very far away from ETABS results. However, there is an option to check it for columns and walls in SAFE it's called : ''Automatic rigid-zone area over column''  When I uncheck it, it gives nearly the exact deflection and beams moment in ETABS This option means the following from CSI america's website : ''Rigid zones are used to model the physical overlap between columns/walls and slab, which prevents deformation of the slab at the column location. This also will have the effect of producing maximum design moments at face of columns/walls instead of center line of columns/walls.  This in turn will produce less reinforcement and hence a more economical design, and allowed by most codes(i.e ACI-318). Deformations also will be more realistic in this case.'' So I assume applying a rigid zone is more realistic but somehow it's not assigned in ETABS and I don't know how to assign it in ETABS.

      What are your thoughts ?
×

Important Information

By using this site, you agree to our Terms of Use and Guidelines.