Ritter’s method – a method most commonly used to determine forces in specific truss members without analyzing the entire truss (as required in the method of joints).
It involves making an imaginary cut through the truss and replacing the removed members with internal forces. If the equilibrium equations (forces and moments) written for the resulting force system form a determinate system, the forces in the cut members can be determined.
In general, three members are cut (one must not be parallel to the other two, and their lines of action must not intersect at a single point). In special cases, more members may be cut (e.g., when some are known to be zero-force members).
We write about Ritter’s method in one of our articles on calculating normal forces in trusses.
