Cover to pilecap bars over the pile
Cover to pilecap bars over the pile
(OP)
Hi,
From the reference of CRSI Handbook(2008) 75 mm cover was provided between pile cap main re-bar and pile, which makes a cover of 150mm from bottom of pile cap to pile cap main re-bar. There was a difference in opinion regarding the above, as some of believe in placing the pile rebar over the pile.
Two things come into play if the bars are set directly on the pile. First is the partial loss of bar development. How much that can be is unknown since the development length equations in ACI include various amounts of clear cover. If the bar were to rest on the pile, the clear cover would be zero over a length of pile. Therefore, a reduction in effective bar area for pile-cap flexure at the pile location would occur. This would reduce the moment capacity of the cap.
Secondly, if the top of the cutoff pile is above the water table, there may eventually be water infiltration around the pile that would tend to produce corrosion in the bars resting on the pile. This will also reduce effective bar area which will further reduce moment capacity. We cannot predict how much this could be.
Some believe the 150mm cover to pile rebar may crack and corrode the rebar in pile cap when water table is above the pile cap.
Could anybody give proper reference from Aci for cover to pile rebar over pile,and also give the best solution for above mentioned.
From the reference of CRSI Handbook(2008) 75 mm cover was provided between pile cap main re-bar and pile, which makes a cover of 150mm from bottom of pile cap to pile cap main re-bar. There was a difference in opinion regarding the above, as some of believe in placing the pile rebar over the pile.
Two things come into play if the bars are set directly on the pile. First is the partial loss of bar development. How much that can be is unknown since the development length equations in ACI include various amounts of clear cover. If the bar were to rest on the pile, the clear cover would be zero over a length of pile. Therefore, a reduction in effective bar area for pile-cap flexure at the pile location would occur. This would reduce the moment capacity of the cap.
Secondly, if the top of the cutoff pile is above the water table, there may eventually be water infiltration around the pile that would tend to produce corrosion in the bars resting on the pile. This will also reduce effective bar area which will further reduce moment capacity. We cannot predict how much this could be.
Some believe the 150mm cover to pile rebar may crack and corrode the rebar in pile cap when water table is above the pile cap.
Could anybody give proper reference from Aci for cover to pile rebar over pile,and also give the best solution for above mentioned.






RE: Cover to pilecap bars over the pile
Could any body answer my previous question
RE: Cover to pilecap bars over the pile