I have two beams spanning 73'-6" in Ram Elements. They act as chords to a horizontal truss and as such experience tension and compression. In sizing the beams, I tried to adhere to the slenderness ratio upper limit of L/300. I ran a model where one of the beams was spliced with fixed ends at the intermediate node and a moment splice connection, and the other beam as a continuous simple span. The spliced beam passes the slenderness ratio check whereas the continuous simple span beam does not. Since the spliced beam has fixed end releases at the splice and a moment connection, it would function in the same manner as the continuous simple span. Why then are the slenderness ratios appearing to be computed differently?
According to the AISC, the length in tension is always the total member length. The unbraced lengths for compression are defined for restraints against buckling and do not play a role. This is our current implementation, in Ram Elements 16.03.00.101. The length (L) used in the L/r < 300 limit is always the full physical member length, not L22 or L33.
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That all makes sense. Perhaps it is more of a theory question and not a RE question as it pertains to slenderness ratios on moment spliced beams; since, it seems like the ratios are computed for the length of the individual beams making up the spliced beam. Though, just looking at it I assumed that the ratio would be based on the total length of the spliced section since the splice rigidly connects the two beam sections.