Space TrussesSpace truss – 3D truss, where connections are made through ball and socket joints.• Simplest shape for a space truss is a tetrahedral shape – 4 triangles.

We can use the same analysis techniques as we did for plane trusses, except that we must now meet the 3D equilibrium conditions.

Method of Joints:

This method is identical as for 2D, except that each force has 3 components and it is necessary to look at all three directions simultaneously.

Method of Sections:

This method is identical as for 2D. Note that each force has 3 components and it is necessary to look at all three directions simultaneously. Do not cut through more than six members, if possible!

It is typically difficult to choose a moment axis that will eliminate all but one unknown. Therefore this method is not used very often.