Allowable stress for a cantilever beam

AI Thread Summary
The discussion focuses on calculating the maximum allowable load and stress for a cantilever beam in a lift design, specifically using AL 6061 T60 material. The horizontal beam dimensions are 3 ft long with a 2x2 inch square cross-section and a wall thickness of 0.5 inches, while the column is 6 ft high with a cylindrical cross-section (OD 4 inches, ID 3.75 inches). Participants emphasize the importance of consulting the AISC Steel Construction Manual for maximum allowable stress values and inquire about the applicability of the manual for aluminum materials. Concerns are raised about the impact of welding on stress calculations and the need to consider lateral buckling as a potential failure mode. Accurate stress calculations require careful consideration of assumptions, moving away from simplistic formula applications.
mdaltayeb
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Hey guys, I'm designing a simple lift in the picture below. I've done nearly all the calculations but i still can't figure out how to calculate the maximum allowable load and stress that the beams can withstand. Also will welding affect any of these calculations dramatically?
say that the horizontal beam is 3 ft long with a square cross section of 2X2 inches and wall thickness of 0.5 inch
say that the column is 6 ft high with a cylindrical cross section with an OD 4inch and ID 3.75
the beams are made of AL 6061 T60.
 

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Thank you for your reply. However, my design is going to be made out of Al 6061 T60. does this book contains tables for this materials ?
is there other ways to calculate the allowable stress without using these tables ?
thanx
 
My copy is in my office. I can check on Monday for you.

Thanks
Matt
 
Stress calculations involve assumptions which will be untrue in every practical situation. In this case, lateral buckling sway is an alternative failure mode you need to consider. Always list and consider the assumptions being made. No more 'formula engineering' please.
 
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