Using Rotations to Obtain Compatibility Equations for Statically Indeterminate Trusses

This paper presents a new way of determining the compatibility conditions for statically indeterminate trusses. It is based on equations relating the angular displacements (rotations) of truss elements to the corresponding extensions obtained by requiring the displacements of the truss structure to be compatible, i.e., single valued. This new angular displacement method is likely to be most advantageous for planar trusses, but less likely so for three-dimensional structures.