] [Thread] [Date] [Author]

[Dave Morris <davem(--nospam--at)endex.com>]

I have a question, particularly for any special inspectors on the list.  For
expansion bolts we have always specified minimum embedment length on our
drawings and schedules.  In Hilti's Product Technical Guide (And I assume on
others) the required hole depth is greater than the embedment by one bolt
diameter.  This is due to the fact that the load is transferred at the wedge
not at the bottom of the bolt.  My questions to the inspectors are this:

1) When you are checking depth of holes are you checking against minimum
embedment or are you checking for the minimum hole depth (which will always
be deeper for expansion bolts).

2) Does it create problems in the field when the plans list only embedment
and not minimum hole depth?  Which would you like to see specified on the
plans? (Both??)  

As a design engineer I am very rarely on the job during anchor
installations.  We depend on the special inspector for these verifications
in critical applications.  My feeling is that we will need to be more
specific on our drawings and schedules so it is very clear that we are
getting the embedment we need.