I have some questions about calculating the deflection of beam. First, when should I applied the method of superposition ? Second, When I'm setting a "x" on the beam, where should I start and end ? Thank you for answering!
1. Whenever it is necessary. 2. Start at the beginning and go to the end. Your questions are overly vague, as are my answers. If you have a specific example to discuss, then you will get more usable responses.
It's not necessary to use superposition. If you had a table of beam deflections and slopes for a cantilever loaded from A to B with a UDL and from A to C with a UDL, you could use superposition to find the slope and deflection for the problem shown. If you are going to work out the slope and deflection using, say, the integration method, superposition would not be as useful.
mchei: In response to your two questions in post 1 ... (1) Superposition is used when a more difficult linear problem can be broken into two (or more) simpler problems. (2) I usually like to start x at the beam left-hand end, and end x at the right-hand end.Superposition might be necessary in a question such as in post 3.
@ NVM Couldn't you create an equivalent loading configuration to make the math easier and not have to deal with superposition at all?