ABSTRACT
In this chapter, the relationships between member distortions and node displacements have been developed for the plane frame element. Therein it is shown how node displacements at the member ends in global coordinates are transformed to those in local coordinates for the member and thence to member distortions. In an analogous way it is found that, generally, axial strains must be considered in frame members in the displacement method when automatic analysis procedures are developed. The complexity which arises in producing displacement patterns and equivalent node forces when bending distortions only are considered is illustrated in the analysis of the gable frame. Transformation equations will be found useful also in certain structures such as the rigid headstock on flexible piles. Fixed supports may be accounted for during the solution of the stiffness equations by simply deleting the corresponding rows and columns of the stiffness matrix.
