I have just noticed a discrepancy in the bending stress reported in a round bar.
I have a 30mm dia bar subject to a Moment of 0.94kNm for which Staad reports a bending stress of 485 N/sqmm
Based on Modulus of pi*D^3/32 =2650 cumm I calculate a stress of 355 N/sqmm.
Am I being thick? (don't answer) Can anyone explain?