Internal Hinge in a Beam
Adding an internal hinge in the graphical screen is very easy.
Choose for the following image in the menu bar: 
In this mode you can add multiple internal hinges by use of the left mouse button. By placing the hinge, the coordinates are shown in the right bottom.
When you add an internal hinge, a new node in the beam is generated, and the regarding beam is automatically divided into two beams with a hinge connection. The beam loads also will be adjusted automatically.
In this way you can easily design a gerber beam.
Look at the demo