ACI-117 rebar placement tolerances
ACI-117 rebar placement tolerances
(OP)
Ties in columns and stirrups in beams are required to be perpendicular to the member. The tolerance for this is stated where???
Occasionally column ties and beam stirrups are fabricated too large in one dimension and as a result can only be placed by "racking". Is there anything in chpt 2.2 of ACI-117 that prohibits this practice. Or anything in chpt 7 of ACI-318?
Reason I ask, have a 2' thick shearwall with #4 cross-ties. Cover should be 1 1/2" each side. Looks like they were fabbed 1'10" which will result in 1" cover each side. A little racking ought to get the correct but what's the limit on this kind of thing?
Occasionally column ties and beam stirrups are fabricated too large in one dimension and as a result can only be placed by "racking". Is there anything in chpt 2.2 of ACI-117 that prohibits this practice. Or anything in chpt 7 of ACI-318?
Reason I ask, have a 2' thick shearwall with #4 cross-ties. Cover should be 1 1/2" each side. Looks like they were fabbed 1'10" which will result in 1" cover each side. A little racking ought to get the correct but what's the limit on this kind of thing?






RE: ACI-117 rebar placement tolerances
RE: ACI-117 rebar placement tolerances
RE: ACI-117 rebar placement tolerances
The cover on the #6 is 2" each side. So the cover on the #11 vert is actually about 2 1/2" or out-to-out about 19". That makes the cross-tie about 2" too long.
RE: ACI-117 rebar placement tolerances
typically, the contractor would just pull out the sledge hammers and pipe benders and the engineer likely would not know of or see such a "fix". i doubt the inspector would see it as long as the contractor didn't do anything extreme. and you could also pull at the midlength of two side to the effectively make the thing short in one dimension.
RE: ACI-117 rebar placement tolerances
i don't have a definitive answer after looking. i suppose you could always take another look at the situation using an equation for sloping stirrups to see what kind of difference it makes in the strength. my personal opinion is that you're not building a watch and if the stirrups are generally level (say within 1-2" of level for 2' depth), then i likely would not raise the red flag. if it looks ugly and appears completely out of whack, i'd start pulling references and contacting the structural engineer to see what they want. as i said before for your situation, an experienced contractor would make it work without it being obvious (whether this is considered right or wrong). if the eor is severely concerned, the contractor should send the stirrups back and get the more correct ones.
RE: ACI-117 rebar placement tolerances
RE: ACI-117 rebar placement tolerances
RE: ACI-117 rebar placement tolerances
RE: ACI-117 rebar placement tolerances
If the wall is also designed to withstand out of plane bending forces, then the effective depth d is greater than 8 in. Check ACI 318-05 Sec 2.2 for definition of effective depth of section. The notation d is also explained in Sec 2.1. For this particular situation, consider it as the distance of the centroid (center) of the verts from the far face of the wall.
Based on ACI 318 Sec 7.5.2.1, the tolerance used to determine minimum acceptable cover is -1/2 in. For a specified cover of 1-1/2 in , the min acceptable cover is equal to 1 in.
RE: ACI-117 rebar placement tolerances