core drillinsert spacing

huangyhg

core drill/insert spacing
hello all, that includes you casseopeia,
i will ask the structural on this project this question, but thought it would be good to get this forum's input.
i have a situation where i will be penetrating a poured in place basement wall with a large quantity of conduit.  these will mostly be 4" conduit, but i also have some 6" conduit and a few smaller ones.  in one location for instance i have 16-6" conduit entering a basement from an on-site manhole.  i intend to penetrate the wall either with core-drilled holes or by using a cast-in-place pvc insert.  the 6" rigid steel conduit requires a 10" opening to allow the installatio of the link-seal assembly.  i have given a sketch to the structural engineer indicting these penetrations in a 2 wide x 8 high configuration.  so he will frame out a 10'-6" h x 2'-6" wide 'window' without rebar for the penetrations if i core drill, or we will cast the inserts in place.
ok, my question is this.  i have indicated a 6" space horizontally and vertically between each 10" penetration.  i assumed that this would be sufficient to allow working space to tighten the link-seals and prevent spauling of the openings if cored.  what would your recommended minimum spacing between core-drilled openings be?  would that change if we used cast in place inserts?
thank you for your patience, regards,
eejaime


i would first see what the general spacing of the reinforcing is in the vertical and horizontal direction and try to accommodate that such that you would have a bar between each opening.

in any case for most basement walls/mats at these hole sizes no particular problem should develop; how less if acting with care and attention to detail. so continue in consultation with the director of the structural works and go ahead.