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Waqar Saleem

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Everything posted by Waqar Saleem

  1. Waqar Saleem
    Dear Hussein, One reason for expansion joint is to avoid shrinkage and temperature cracking, basically expansion joint is a weaker zone intentionally created to direct the cracks or release the stresses due to hydration of cement. if concrete dimension is 150ft-200ft, it is advisable to provide expansion joint or shrinkage strip to avoid shrinkage/temperature cracking. To avoid cracks try to have proper mix design from a material engineer, sometime excessive cement content has been used in mix and assumed that this extra cement will give strength but thats not true, I have seen adverse temp cracks in 500ft long 15' high basement retaining wall, even wall was not loaded vertically or backfill, mix had extra cement content and there was no expansion joint in the wall along the length. Regards
  2. Waqar Saleem
    Dear Ahsan, 1-If you are excavating 10'(say) from NSL,soil strata is under load of this much soil 10x120=1200psf, you are provided bearing capacity at -10 by the geotech, 1tsf=2204psf, you can add 2204+1200=3404psf for bearing pressude check, but discuss this condition to your geotech, also there is safety factor of 3-5 in geotech calculations, decreasing this FOS to 2 or at some lower value as geotech allow, earing pressure issue can be addressed. 2-define a stiff element in safe where you define your foundation section, and assign the area below basement wall as stiff. Regards
  3. Waqar Saleem
    Dear Rummaan, It is ok to detail the pit as you have shown in snap and model the raft bottom at same level in SAFE for ease. Regards
  4. Waqar Saleem
    Dear Ahsan, 1- consider the relieving pressure of soil as your model shows basement. 2- provide stiff element at the edges of raft as there is basement wall all around. 3-increase in thickness also decreases the pressure, check increasing raft thickness. 4-make sure that actual raft area is provided in SAFE, sometimes it is mistakenly considered less when raft is drawn on center points of the columns, actually you should provide the offset of half column width or depth as per condition on edges. 5- check loads applied on the floors, finishes, walls, decrease where-ever you can, make deduction of windows and doors, check if lighter elements are available, decrease thickness of slabs if possible. 6-Add one column in between all grids if possible, 7-offset your columns some distance 2' or 2.5' inwards, ask the architect, share your problem. 4-if none of the above options and solution provided by seniors work, have review of geotech and go for piled raft. Regards
  5. Waqar Saleem
    Dear All, Is it possible to tell about a beam section from looking at its top and bottom reinforcement that either it is singly reinforced or doubly reinforced? no other information is provided, only top and bottom bars are provided say 3#4 Top, 3#6 Bottom, B 12"x18" . Regards
  6. Waqar Saleem
    Dear Hamza you have to tick the specified load pattern and specify load patterns Dead, Super dead or Live with their multiplier factor or tick the other two, you do not have to tick all three. Regards
  7. Waqar Saleem
    Salam Dear Junaid! Cold joints are common and practice is upto soffit, properly roughen the face and apply some chemical at the joint. Leaving column at mid height is not good. Regards
  8. Waqar Saleem
    Dear Shafqat Hussain Welcome to the forum. Check what you require at the job and discuss with your seniors, ask them for help if you do not understand something. At first job mostly you don not know exactly what to do but the main engineering profession skill is lifelong learning which comes forward and you learn new things. Contact some senior surveyor for the level and theodolite guidance. Regards
  9. Waqar Saleem
    My kid is 2 nd 3 months old, we normally try to keep screen time as low as 1 hour/ 2 hour, when he watches cartoon or use mobile for game more than 2 hours, he becomes too difficult to handle. So we bought books that we read with him like picture stories and take him outside where he can play, run and climb monkey bar etc, after playing he becomes satisfied and easy to handle. that's my personal experience :-). Regards
  10. Waqar Saleem
    Salam Makhzumi Screen time should be minimum but it should be replaced by healthy outdoor activities. Children become addicted to screens that's dangerous, we can not force them to reduce there screen time but provide them with healthy alternatives can change there interest. Regards
  11. Waqar Saleem
    if they insist for dwg provide them along-with pdf, take receiving on this pdf printout.
  12. Waqar Saleem
    yes, in Pakistan some authorities require soft CAD copy. Provide them read-only CAD file, they can not alter or tamper it. Regards
  13. Waqar Saleem
    Muneeb, here is my view though seniors have explained above nicely. 1.what is the value of subgrade modulus ? in some cases using subgrade modulus with 2" settlement solve the issue of over-stressing under foundation. As normally value for the SM given is with 1" settlement when we calculate by the formula given in Bowles, as Geotech to provide you the value or simply multiply the value by 2 which is calculated from the bearing capacity 0.5*3*12*2204*2 lb/ft^3 . 2. if you have basement then assign stiff to the foundation under rcc basement wall. 3.check your applied loads, make them realistic and compare with reactions, check your load combinations; sometimes load combos are assigned greater factors mistakenly or by abrupt system shutdown induce some error in them. 4. increasing thickness of raft also decreases bearing pressure, try. Regards
  14. Waqar Saleem
    Dear Jaher Make a grid for the required wall and draw the wall in elevation or 3d view, in plan view slanted wall will not be drawn. Regards
  15. Waqar Saleem
    Dear Jaher I guess, It is possible to have a slanted shear wall if it is properly connected at different levels, and modelling is also possible in etabs or sap.Regards
  16. Waqar Saleem
    Salam Members, Congratulations to Engineers, PEC has become full signatory of Washington Accord, what are the benefits to Pakistani engineers for this agreement. Regards
  17. Waqar Saleem
    Muneeb, if mass source is not defined properly, seismic forces will not be calculated correctly and so the base shear value will also be incorrect. Selecting different options in mass source menu is quite fine if loads has been taken in consideration as mentioned above 100% dead and 25% live in case of warehouses or permanent live loads. Regards
  18. Waqar Saleem
    This polls concludes that on this forum majority is from NUST :-), other universities are doing very good job in engineering development as well.
  19. Waqar Saleem
    Salam i would like to ask how much minimum investment is required and what is the return rate? or what should be minimum amount to start investing in PSA for a reasonable return?
  20. Waqar Saleem
    Salam Request to the admin and open to comments/suggestions from other senior members. I suggest there should be an open monthly/bi-monthly/tri-monthly meeting of forum, city based, with the members available in different areas of the country. This is necessary to improve the activity on the forum as well as concrete output from the discussions on the forum. At first Rawalpindi/Islamabad City circle may arrange a meeting after eid , i propose the date 8th,9th july, second weekend after eid. Out-city members are also invited to attend the meeting.
  21. Waqar Saleem
    i volunteer myself for any kind of job for the SEFP !!! i can convince some members also to whom i have personal interaction.
  22. Waqar Saleem
    Thats great!!! SEFP VIP i liked most.
  23. Waqar Saleem
    footing is of 6ft thickness for which i proposed more than 2 layers of temp/shrinkage reinf.
  24. Waqar Saleem
    this provision is not applicable to minimum shrinkage temperature requirements case. temperature/shrinkage reinforcement should be placed in 2 or 3 layers from top to bottom, because just two layers at top and bottom will not serve the purpose and shrinkage cracks will definitely propagate.
  25. Waqar Saleem
    A catastrophic event of landslide, slope cutting without protection is very dangerous, one should avoid or keep proper considerations. VID-20170511-WA0009[1].mp4
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