Beam Deflection Question
Beam Deflection Question
(OP)
Hi all,
I've been working through some designs at work, and I came across a condition of loading where I was unsure of the way to calculate actual deflection. I had 3 unequal point loads, unevenly spaced.
For example:
l = 10ft
P1 = 1kip
x1 = 1ft
P2 = 2kip
x2 = 3ft
P3 = 1.5kip
x3 = 7ft
At first, I figured a simplified way to calculate this was complete a deflection calculation of each individual deflection and sum the results. Would this provide a close enough, preferably more conservative, deflection calculation?
I've been working through some designs at work, and I came across a condition of loading where I was unsure of the way to calculate actual deflection. I had 3 unequal point loads, unevenly spaced.
For example:
l = 10ft
P1 = 1kip
x1 = 1ft
P2 = 2kip
x2 = 3ft
P3 = 1.5kip
x3 = 7ft
At first, I figured a simplified way to calculate this was complete a deflection calculation of each individual deflection and sum the results. Would this provide a close enough, preferably more conservative, deflection calculation?






RE: Beam Deflection Question
Sometimes for a quick first run I'll sum the loads and apply then as a single point load at midspan. I've got that deflection formula memorized. If that beam size comes back reasonable, then no need to go further.
RE: Beam Deflection Question
BA
RE: Beam Deflection Question
http://webstructural.com/beam-designer.html
R.Efendy
RE: Beam Deflection Question
RE: Beam Deflection Question
RE: Beam Deflection Question
I'm familiar with Alex Tomanovich's "BEAMANAL" spreadsheet, but I am not familiar with the (P*(L-a)^3)/(6EI) equation he uses for multiple point load situations. I figured it could have been a simplification towards a more conservative route.
RE: Beam Deflection Question
I think it is a good "waste of time" to do the hand calcs yourself at least once.
I think it's an excellent idea to look at different ways of applying these loads (like a single mid-span load (most conservative) or as a UDL (least conservative) to develop your own feel for the solution (and not rely on something you read on the internet)
another day in paradise, or is paradise one day closer ?
RE: Beam Deflection Question
It will hardly take a few minutes to get the equation for the deflection at any point using double integration/McCaulay's method.
equating the slope equation to zero, the location of max. deflection and thereby he max. deflection can be found.
RE: Beam Deflection Question
RE: Beam Deflection Question
another day in paradise, or is paradise one day closer ?