DE shuttering Period As per IS 456

 DE shuttering Period As per IS 456



About De shuttering 

While the above criteria of strength shall be the guiding factor for removal the form work ,in normal circumstances where ambient temperature does not fall bellow 15'C where ordinary Portland cement is used and adequate curing is done , following striking period may deem to satisfy the guide line given bellow.

  1. Vertical form work to column, wall and beam de shuttering form work is 16-24 hours.
  2. Soffit form work to slabs De shuttering form work striking is 3 Days.(props to be refaxed immediately after removal of form work )
  3. Soffit form work to beams De shuttering form work Striking 7 Day's (Props to be refixed immediately after removal of form work)
  4. Props to Slab
  5. Props to beam and arches  
  •  Spanning up to 4.5m De shuttering 7 Days 
  • Spanning over 4.5m De shuttering  14 days 
      6. Props to beam and arches
  •  Spanning up to 6m De shuttering 14 Days. 
  • Spanning over 6m De shuttering 21 Days 
           For other cements and lower temperature the striping time recommended above may be suitable modified.
       
           The number of props left under their size and disposition shall be such as to be able to safely carry the full dead load of slab, beam or arch as the case may be together with any live load likely to occur during curing or further construction.
           Where the shape of element is such that the form work re entrant angle the form work shall be remove as shoon as posible after the concrete has set avoid shrinkage cracking occurring due to the restraint imposed.

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