Statics question - application of fixed end moments
Statics question - application of fixed end moments
(OP)
I'm brushing up on statics before taking the SE exam. In the attached pdf of a fixed end beam with a non-center point load, in the past if I summed the moments at point B I would find:
EMb = 0 = -Ra*L + Pb - Mb
Would you or would you not also include Ma in this equation? I would not consider the moment Ma to create a moment at point B but according to page 9 of the following link the moment Ma does create a moment about Mb: http://ocw.nthu.edu.tw/ocw/upload/8/259/Chapter_10...
Is it incorrect to assume that the upward rotation caused by moment Ma would not be cancelled out by the concentrated force P and therefore the moment Ma would not create a rotation at point b? What do the experts here think?
EMb = 0 = -Ra*L + Pb - Mb
Would you or would you not also include Ma in this equation? I would not consider the moment Ma to create a moment at point B but according to page 9 of the following link the moment Ma does create a moment about Mb: http://ocw.nthu.edu.tw/ocw/upload/8/259/Chapter_10...
Is it incorrect to assume that the upward rotation caused by moment Ma would not be cancelled out by the concentrated force P and therefore the moment Ma would not create a rotation at point b? What do the experts here think?






RE: Statics question - application of fixed end moments
In general if you are using equilibrium to determine forces, then you need to include all the applied loads and all the reactions.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: Statics question - application of fixed end moments
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Statics question - application of fixed end moments
you should absolutely include Ma in the sum of moments ... after all, you are summing all moments on the beam; you neglect Rb 'cause the moment created about b is zero.
another day in paradise, or is paradise one day closer ?
RE: Statics question - application of fixed end moments