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I was modeling a not so regular mat footing in SAFE software.The position of column was changed accordingly per grid but the main problem was when the design strips moment was checked along x direction,the following problem occured as shown in figure because previously the grid was maintained to the standard template.I went to Interactive data editing,but couldnt figure out the actual problem,Please help me how do I actually get this solved?Another problem was when I went to Design tool and changed punched shear overwrites for interior column different behavior or edge column behavior,I was not able to retrieve the same value as from the manual calculation.Another though on it was ,Is defining subgrade modulus of soil necessary ?what to do if only bearing stress is mentioned in the question.Please go through the attached figures herewith.Thankyou ,sep 






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  • Our picks

    • *SEFP Consistent Design*<br style="color:#272a34">*Pile Design*<br style="color:#272a34">*Doc No: 10-00-CD-0005*<br style="color:#272a34">*Date: Nov 21, 2017*<br style="color:#272a34">

      This article is intended to cover design of piles using Ultimate Limit State (ULS) method. The use of ULS method is fairly new for geotechnical design (last decade). The method is being used in multiple countries now (Canada, Australia etc). The following items shall be discussed:


      Geotechnical Design of Piles (Compression Loads, Tension Loads and Lateral Loads)

      Structural Design of Piles (Covering both Concrete and Steel)

      Connection of Pile with the foundation (Covering both Concrete and Steel)

      Pile Group Settlement

      Things to consider


      1. Overview

      Piles provide a suitable load path to transfer super-structure loads to foundation where shallow foundation are not suitable - this can be due to a number of reasons like existing space constraints or suitable soil strata is not present immediately below structure. Other uses can be to meet design requirements like to have reduced settlement etc.

      This article shall cover the use of straight shaft cast-in-place concrete piles and straight shaft driven steel pipe piles. There are a number of additional piles types like belled concrete piles, precast concrete piles, screw / helical steel piles etc but the discussion to choose a suitable pile type is not in the intended scope of this article. The article is intended  to discuss design requirements for straight shaft piles only (both concrete and steel) . The aforementioned topic about pile selection is a very diverse subject and requires a separate discussion on its own.

      Click on the link to read the full article.
      • 9 replies
    • 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.



      • 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

      • 10 replies
    • Salam Members,

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




      • 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
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  • Similar Content

    • By ILYAS
      There are issues which needs to be addressed:
      1-Why there is much difference in punching shear results in SAFE and ETABS models considering same parameters in both models.(same modifier, same geometry,same assignment of shell behavior in both cases  though SAFE does not have the option of thin shell all other the input is same),i have checked both the cases when the automatic rigid zone area over the column is on and the second case is when this option is off.
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      How to check Punching Shear in a flat slab in SAP2000? Is there some direct command as in SAFE?
    • By waqar saleem
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    • By mhdhamood
      I argued with a senior Engineer about the punching shear check for shear wall; As far as I know :

      1. The shear wall will attract high moments.
      2. Also in the case of design itself, the controlling case from a combination that contains Earthquake will be the tension axial force not the compression (Please Verify or disagree!!!)
      3. If I want to check punching for this shear wall I will take the moment at the Top of the shear wall (pier)
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      6. Please help me in this subject. I am sure the shear wall in earthquake will suffer from high moments which in case cause punching need to be counted for .

    • By mhdhamood
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    • By mhdhamood
       Dear all
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      1. Since its definition is a wall then there is no need to check punching.right?
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      the problem i am facing is that safe is showing punching shear ratio values of the shear wall on which the slab is resting.
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    • By mhdhamood
      Dears seniors;
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    • By dr.tatish
      Dear Esteemed Fellows users of Safe program:
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      Referring to the attached picture, Is there any mistake in the sign of the considered moments in the punching result sheet and the correspondent moments signs appeared in the output results of the considered column.
      Remember that the main axes of the considered column are the default ones of Safe; axis 2 is parallel to the X axis and the axis 3 is parallel to the axis Y.
      The attached picture is a snapshot of the example BS 8110-97 RC-PN-001.FDB came with Safe-Verification-Design Examples.
      Your participation and feedback are deeply appreciated, thank you very much indeed.

    • By dr.tatish
      Dear Madams/Sirs:
      I am looking for the following ACI  two supplementary documents: ACI 352.1R-11 and ACI 421.2R-10.
      Best regards. 
  • Recent Discussions

  • Latest Forum and Club Posts

    • I have a query , that in Flat slabs , as we have only supports in shape of columns,  where we may give overlaps of bottom mesh and top mesh ?  may it be showed through drawing please ?
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