A structure usually consists of a large number of load bearing elements that need to be joined together. When rigidly connected, such a joint has to transfer three section forces (one axial force, two shear forces) and three moments (one torsional and two bending moments). Depending on the type of material such full connections are sometimes (e.g. for wood) hard to achieve, costly and bulky. A solution to this problem consists in introducing hinges.