Initial Strains in the Matrix Force Method of Structural Analysis

In a Technical Note in the June Journal (p. 354), Dr. A. L. M. Grzedzielski discusses some aspects of the Matrix Force Method of Structural Analysis and in particular has raised objections to the concept of initial strains and its use by the present writers as an artifice in the treatment of cut-outs and modifications in structures. Dr. Grzedzielski asserts that the idea of initial strains is not valid if the flexibility matrix of the unassembled structural elements is other than purely diagonal. Unfortunately this assertion is just not true.