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Re: closure strip connection to wall fixed or hinged? [post tensioned flat pl...

[Subject Prev][Subject Next][Thread Prev][Thread Next] Scott,

The design of closure strips typically involves a lot of approximation -
other than that there probably is no `typical design'.  

Since most (or all?)  of the post-tensioning design programs don't handle
closure strips real well, alot of engineers do a run assuming the slab is
continuous and then design the steel based on the calculated moments.  In
actuality,  the slab is probably hinged, both at the slab/closure strip
intersection and at the closure strip/wall intersection.

Reinforcement corrosion is a concern anywhere you have a joint in a parking
garage.  The most important issue with respect to closure strips is that they
be left open long enough so that the majority of the slab shrinkage has
occured.  The  time the strip is to remain open should be specified on the
design drawings, it should not be left up to the contractor to decide.   As
the plan reviwer,  I think you would have the authority to require this be
shown on the drawings since it is related to restraint of the slab.

I don't know if you have the authority to require that the reinforcing be
epoxy-coated or that a corrosion inhibitor be used in the concrete for the
the closure strip.  These are more `durability issues'  than structural
issues and opinions about the effectiveness of both of these options vary.  
It is not a bad idea for the joint along the slab/closure strip intersection
to be routed and sealed and for there to be cove sealant at the closure
strip/wall intersection but again I do not know if you have the authority to
require this.

Since this is a parking structure, I am assuming that encapsulated tendons
are being used.

Gail Kelley