Opening The Black Box: Direct Stiffness Method Uncovered

This paper describes our use of common computer tools to help students unlock the mysteries embedded in structural analysis computer programs that are based on the Direct Stiffness Method. The methodology described in this paper is taught in an Advanced Structural Analysis course in the ABET-accredited civil engineering program at the United States Military Academy. This formulation is based on our strong belief that students must understand the basic assumptions inherent in the Direct Stiffness Method before they can confidently and competently perform computer-based structural analyses. We find that students understand these assumptions best when they have an opportunity to work through each major step in the Direct Stiffness Method by hand—aided by appropriate software to perform computations and matrix manipulations.