Minimum deflection of beam - posn of supports calc
Minimum deflection of beam - posn of supports calc
(OP)
I know this is a trivial question, but I vaguely remember noting a ratio for the quick positioning of a pair of supports under a uniformly loaded uniform beam such that deflection of the centre and equal overhanging ends is minimum.
Am I dreaming this, or can anybody recall it, please?
Oh, I guess I could figure it, but it's more fun to ask!
Cheers to all.
nigelt
Am I dreaming this, or can anybody recall it, please?
Oh, I guess I could figure it, but it's more fun to ask!
Cheers to all.
nigelt
"The ideal client is one possessed of great good sense and perfect judgement;
that is to say, one who agrees entirely with the designer at all times and in every respect."
Fenwick Williams, Naval Architect.






RE: Minimum deflection of beam - posn of supports calc
I don't know about minimum deflection, because it depends on the second moment of area you are using, but I have a formula in my book of notes, which says -
For a uniformly distributed load, deflection at centre of beam to equal deflection at ends of beam, place supports at 0.553 x Length of beam.
I have never tried this, so don't know how accurate this is. Maybe you could do your calculation and report back.
Regards,
Neilmo
RE: Minimum deflection of beam - posn of supports calc
RE: Minimum deflection of beam - posn of supports calc
For equal stresses, I have support spacing = 0.586 x Length of beam. This is close to your 0.6.
REgards,
Neilmo
RE: Minimum deflection of beam - posn of supports calc
Have just checked my support spacings above on a beam program that I have and they work out just fine -
Equal deflection support spacing = 0.553 x Length
Equal stresses support spacing = 0.586 x Length
Neilmo
RE: Minimum deflection of beam - posn of supports calc
Thanks... more stuff to add to the back cover of my steel handbook.
RE: Minimum deflection of beam - posn of supports calc
Neilmo
RE: Minimum deflection of beam - posn of supports calc
Best regards,
Nigel T