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Re: closure strip connection to wall / cantilevered construction

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

As a side comment on your question,  I am not sure how you are calculating
your propped cantilever moment.  Calculations can be a little bit complicated
since the way the slab is shored can have an effect on its behavior.

If you have some calculations you could summarize or fax (801-881-6698)  I
might be able to comment further (although not necessarily intelligently).

Note that when you design a cantilevered post-tensioned slab or slab section,
there is actually no vertical reaction at the cantilevered end.  Tyipcally,
the tendons are profiled so that they are concave down over the support,  
there is a point of inflection about span/10 from the support and then the
tendons are concave up (or flat) to terminate at the centroid of the
cantilever edge.

There thus is just an axial compressive force from the tendons at the slab
edge.  Obviously,  this will change once the closure strip is cast.  It is
not obvious exactly how this will change, however, since you are essentially
dealing with composite construction.  For example if the shoring was not real
tight and the cantilever has deflected,  the slab is nominally only
continuous for live load and the weight of the closure strip.

Gail Kelley