Sorry, I think u misunderstood me... I refer to the thread below...SteamKing said:There is no moment applied at point A, so there won't be one showing up on any moment diagram.
There is a moment applied at point B, which is why the moment diagram starts there.
SteamKing said:If you look at the moment plot at C, it clearly indicates that the reactive moment there is -400 N-m, which, when added to the moment at B of +400 N-m, equals zero net moment.
Do you mean that since the moment at B is positive 400Nm, so the moment -400Nm must be restricted at any points along beam BC to keep it in equilibrium?
Your interpretation of what the plot would look like would require a net change in moment of -800 N-m, which is not supported by the loading of the beam.
sorry , can you help me in the following threadSteamKing said:There is no moment applied at point A, so there won't be one showing up on any moment diagram.
There is a moment applied at point B, which is why the moment diagram starts there.
it it because of the reaction moment and moment causes the part of beam to become concave downwards, so bending moment is negative?SteamKing said:It's not clear what you mean here.
The moment diagram doesn't plot discrete values of BM in isolation, like you apparently want to do.
At point B, the moment goes from 0 to +400 N-m, which is why there is a jump at this location.
The moment remains constant at +400 N-m from point B to point C, where the reactive moment of -400 N-m is added to the +400 N-m, to bring the net moment back to zero.
You should review how shear force and bending moment values are plotted for regular beam problems.