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  6. Check the following link. May be it could help. Regards.
  7. Does anyone have the soft version of Muni Budhu? If not then any other book which describes the pile foundation topic in such detail as in Muni Budhu.
  8. Legit request. Find attachment. 2011-12-lateral-stability-of-purlins-and-girts.pdf
  9. In addition to pushover curver (Base shear Vs displacement) SAP gives you the option of ATC -40 curve. So you can select that. Then go to the properties table of the curve and you can get the Sa and Sd values.
  10. Salam, What is the difference between the under reinforced and tension controlled section? Are they same with the exception of strain values of steel.? Many Thanks
  11. Can you add the reference, from where above excerpt has been taken? It is always a good idea to indicate the reference, whenever an excerpt is quoted to explain some technical matter or concept (especially when it is taken from some book or code). This helps the reader to consult the original reference and study in more details, if required. Regards.
  12. You can model sag rod as bracing (Sag rod properties can be defined in a frame section and modelled as a brace) provided your design condition allows the sag rod to behave like a brace as I mentioned in the previous post. Once you model them, see the forces and design accordingly.
  13. The horizontal members are the ones which will be braced using sag rods. yes its elevation view. We have similar horizontal member at the other side too and the 2 are to be braced using sag rods. Design of sag rods will be similar to that of cables, not sure if SAP2000 can design it accurately or at all, never did it. Or do u have anything on design of rods or cables in SAP2000?
  14. Can you please explain the image. What view is this.. looks like a elevation but what are we looking at? You can model sag rods but arrangement is key to understand if they are acting as discrete bracing or not. Read my reply below. I don't agree with your statement. How can they offer "vertical restraint"? Sag rods can act as "discrete bracing". Read the excerpt below:
  15. I think Uzair has replied to your question well. I was about to say the same thing for number 1 after checking my self. Try using a 4x4x1/2" or 3x3x3/4" as bracing. For top and bottom cord, go with a lightweight 8" section (like W200x36). Using 8" will allow you to do field bolts easily as 6" or less are tight for even 2 bolts. For L/r > 60, I am not sure what that is.
  16. @lora_azar ماله

  17. Sag rods will restrain translation, you can draw points where sag rods are connected, divide the frames at those points and apply vertical translation point restraint only.
  18. you can even use etabs for this.
  19. I have a model from a client to review. There are these horizontal members that are having the P-M Ratio value as greater than 1. Showing that the members are over stressed. Now the client asked me to ignore it, as these elements will be braced by the sag-rods but that they cant be modeled on SAP2000. Is it true that we can't model sag-rods on SAP? If yes, then how can I check that whether these sag-rods will reduce the P-M Ratio of these elements to 1 or not?
  20. 1. Sections used earlier: Channel 6"x 3" for top & bottom chord. Later changed to double-channel 6" x 3" back to back. 2x2x1/4 angle for bracing. Later changed to double-angle 2x2x1/4 back to back. Changed further to bigger sections...... In steel design sheet it says ..... Warning l/r > 60, Check bracing at beam-column connections.
  21. For Seismic Design requirements, you may refer to AISC 341-10 specification, that can be downloaded from here for free. Seismic compactness requirement are given in Chapter D. In order to avoid above error, you will have to try ONLY those sections that are seismically compact according to AISC 341. To avoid this error, the slenderness ratio (l/r) of the steel sections to be used for concerned members must not exceed 60. You will most probably need to reduce spacing (or increase number) of column bracing for this purpose. Regards.
  22. 1) What are the section sizes that you are using. Please list the original ones as well as the updated ones. 2) What is the Sap2k error code of l/r > 60 message?
  23. During the seismic design of this truss, following errors are displayed: vertical Sections are seismically non-compact. (I changed to bigger sections but still in vain.) l/r > 60, Check bracing at beam-column connections. (Columns are braced at mid height but still in vain.) I would appreciate any thought on the subject.
  24. thank you for your positive response
  25. Yes thanx alot. It was really helpful.
  26. Earlier
  27. 1. Section 1.3.1 of AASHTO's Guide Specifications for Design of Pedestrian Bridges, 1997, states the following regarding the deflections:- "Members should be designed so that the deflection due to the service pedestrian live load does not exceed 1/500 of the length of the span. The deflection of cantilever arms due to service pedestrian live load should be limited to 1/300 of the cantilever arm. The horizontal deflection due to lateral wind load shall not exceed 1/500 of the length of the span." On the other hand, Section 5 of AASHTO's LRFD Guide Specifications for Design of Pedestrian Bridges, 2009, describes the following regarding the deflections:- "Deflections should be investigated at the service limit state using load combination Service I in Table 3.4.1-1 of AASHTO LRFD. For spans other than cantilever arms, the deflection of the bridge due to the unfactored pedestrian live loading shall not exceed 1/360 of the span length. Deflection in cantilever arms due to the pedestrian live loading shall not exceed 1/220 of the cantilever length. Horizontal deflections under unfactored wind loading shall not exceed 1/360 of the span length." 2. AFAIK ETABS 2016 can design steel connections. However, SAP2000 does not have this option. Regards.
  28. The attachement is an steel truss access bridge on a earthen dam. What I want to ask is following: What should be the max. allowable vertical displacement in this case? How can I design the connections in SAP2000? Please say whatever you feel like....... constructive criticism. I'm all ears. New Picture (1).bmp New Picture (2).bmp
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