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RE: Clip angle connection to concrete

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>I've seen other engineers just design
>for shear in [shear] connection design.
>What is the basis for neglecting the
>eccentricity?

There is an explanation of this in a textbook (by McGuire, I think) that
postulates that bolted connection design originated from riveted connection
design, which developed at a time when analysis methods were not
sufficiently advanced enough to handle the complications of things such as
eccentricity. As a result, basic limits were established to bound simplified
solutions that ignored eccentricity. The explanation goes on to comment that
the development of welded connections came at a time when analysis methods
had become more advanced and eccentricities were included because they could
be.

Today, much of those historic practices remain. We have gage limitations
andeccentricity ignored within those limitations or bolted sher connections
and eccentricity considered explicitly for welded connections.

As far as your case, I'd based my decision on whether eccentricity can be
ignored based upon how forgiving the assembly is. Some drilled-in anchors
have very sudden modes of failure, while others have significant ductility
or reserve strength. Steel-to-steel bolted joints are extremely forgiving
since all components offer significant margin for ductile redistribution and
mitigation of the slight eccentricities, and very often reserve strength.
For example, the angles flex and relieve the moment while the bolts in the
outstanding legs can handle to the increased demand of the small tensions
that might develop even though they were only designed for shear. The
flanges and webs connected also provide some forgiveness because they can
often deform slightly.

These benefits may or may not be true in the case of an attachment to a
concrete element.

Charlie

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