One of the criteria for lift lug design is to check
the tension on the net section passing through the
pinhole. AISC (ASD) Section D3.2 states: "For
calculation purposes, the distance from the edge of
the pinhole to the edge of the plate...., shall not be
assumed to be more than 0.8 times the diameter of the
pinhole". (Please note that in the original
publication a factor of 1.25 was printed which was
subsequently corrected to be 0.8 per Errata issued by
AISC). Also, the maximum width from the edge of the
pinhole is limited to 4 times the plate thickness.
Therefore, in order to satisfy this criterion (tension
capacity), one can increase the pinhole diameter or
increase the plate thickness. In a design I completed
recently, I chose to increase the hole diameter: The
pin diameter was 2.5" and the hole diameter came out
to be 5". The design, while technically correct,
seemed odd because of a large hole to accommadate a
smaller pin. Am I missing something?
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