Pour strip and contraction joints

[ramihabchi]

Hello,
I read the following thread507-146604
Where it have been said that pour strip, in case slab is restrained are adequately spaced if spacing is less than 30m or 100'
My questions are the following:
1)does ACI recommends maximum lengths without pour strips?which one because I can t find it in ACI 224.if not which code in US should I refer to to see recommendations?
2)if pour strip or contraction joints are used adequately(as recommended by ACI) should I still use temerature and shrinkage reinforcement?or putting shrinkage and temperature reinforcement required by aci would enable me to eliminate contraction joint/pour strips

 

[JAE]

ramihabchi,

1) I think the spacing of pour strips in post-tensioned slabs depends on general engineering judgement - not a code provision. I don't know what the typical spacing might be but usually you separate the slab from any attached, stiff element like a stairway shaft wall system or an elevator shaft where the stiff walls would resist the normal shrinkage due to the posttensioning.
2) Pour strip placement doesn't, to my knowledge, alter what is required for Temp/Shrinkage.

Anyone else have thoughts?

 

[r13]

JAE,

See OP's another thread posted on "ACI Code Issues" forum. Link

 

[HTURKAK]

Pour strip , is a temporary separation of approximately 40 in. between two regions of slab that post-tensioned separately.After post tensioning ,the regions are allowed to undergo shortening. After 30 to 60 days, the gap is filled with non-shrink concrete.

Pour strip is also used at high rise buildings with podiums, when the raft foundation is not founded on sound rock or on piles. The pour strip is provided at raft between tower and podium to reduce the differential settlement effects. The gap is filled after the süper structure concrete works completed .