Statically Determinate Trusses Programmed in Logic

Classical methods of structural analysis play an important role in the understanding of the behavior of structures because, during the process of solution, the conditions of equilibrium and compatibility are used explicitly. Computationally, these methods are problem dependent and, thus, are not suitable for algorithmic programming. Logic programming can be used to implement classical methods of structural analysis. This approach can help students understand the conditions of equilibrium and compatibility for structures and, at the same time, formulate the problem on a modern base from which design considerations can be tackled by using artificial intelligence methods and expert systems. The analysis of statically determinate trusses is employed to demonstrate the logic approach. The goal of solving a truss problem is achieved through the same subgoals followed when solving the truss problem by hand calculations. The procedure can be traced in a transparent way and alternative paths of solution can be determined. A program written in Turbo Prolog is presented and the logic approach is illustrated with some examples.