Structural reanalysis for general layout modifications

A procedure for reanalysis of structures subjected to various layout modifications is presented. The procedure is based on exact analysis of the initial design. It is suitable for all types of layout changes, including the general case in which some members and joints are added, other members and joints are deleted, and some joint coordinates are modified. In the particular and challenging case of addition of joints, where the number of degrees of freedom is increased, a simple reanalysis of a modified initial design Is first carried out. Further changes are then applied to the latter design. It is shown that, for changes in a limited number of members of a truss structure, an exact solution is readily achieved. For changes in numerous members of a general structure, an approximate solution can he efficiently obtained. High-quality approximations are demonstrated for various types of layout modifications.