This software is an excellent free bridge design software. It runs on Windows PCs and can be downloaded from there website: http://bridgecontest.usma.edu/ This is the description from their site: “The West Point Bridge Designer 2007 will introduce you to engineering through an authentic, hands-on design experience. This software provides you with the tools to model, test, and optimize a steel highway bridge, based on realistic specifications, constraints, and performance criteria.