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  • John Mark B.
    Participant
      August 4, 2007 at 3:13 pm #2889
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      Hi all,

      What are the consequences if the PT slab (bonded system) is not being grouted after completion of final stress because of some constraints?

      Ronaldo
      Participant
      Posts: 22
        September 30, 2008 at 10:13 am #3188
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        hello sir, i think if bonded system will be behave like unbonded system. so disadvantage of unbonded is that cutting of member will make failure of member due to cutting of tendons..

        Ronaldo
        Participant
        Posts: 22
          October 11, 2008 at 7:55 am #3190
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          and one more thing to add is in unbonded stresses are transferred to member through anchorage system while in bonded tendon directly transferred to member through grouting. Inshort will not gain effective stress if not grouted.

          Thanks…

          IjazzGul
          Participant
          Posts: 20
            November 7, 2008 at 1:23 am #3197

            …and don't forget that un-grouted bonded tendons are subject to corrosion due to possibility of contact with air..

            ahmed
            Participant
            Posts: 31
              January 31, 2009 at 2:26 am #3198
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              In my opinion, the results would be poor if using the same diameter sheathing. I believe that if you were to be unable to grout the cable that it would be useless. The space between the cable and the sheathing will allow too much movement of the slab. I myself…having done repairs, drying, greasing, tensioning, removal, installation and regrouting with epoxy, do not believe in grouted cables due to their inablilty to be maintained. unfortunatly grouted cables do still corrode, and DO still come in contact with water and moisture. At which point drying said cable becomes a royal pain in the ass, and regrouting becomes a near impossibility. there is no epoxy or grout available on earth that is thin enough to be pressure grouted throughout the length of a post tension cable. Unless the slab for a dollhouse. in short, you need to grout cables to spec.

              Ronaldo
              Participant
              Posts: 22
                February 9, 2009 at 11:39 am #3200
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                …consequence for the tendon not grouted after final stress….one most practical answer might be….the more the time the strands are exposed , unbonded ( without grout ) the more the time we are giving possibilities for the corrosion to form in.

                Administrator
                Keymaster
                Posts: 66
                  April 7, 2009 at 5:27 am #3207
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                  Add one thing also of tendons are failed structure will be damaged

                  Decipher
                  Participant
                  Posts: 46
                    April 10, 2009 at 9:21 am #3210
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                    Hi All,
                    In bonded system it is very necessay to grout after final stressing as the strands will get corrode and it will create problem in structure of PT slab in future years, also strands which are stressed and taking individual load in particular tendon by which grouting in that tendons will act like a bond in the tendons. Also with in 25 to 30 days (maximum) of final stressing grouting is v necessary.