OPTIMIZATION OF BRIDGE FORMS

Abstract

One of the most fundamental parameters that determine the efficiency of a structural design is the form of the structure. Absence of the best geometry, interconnectivity, and disposition of the members to resist the loads, is crippling to any improvement that can be otherwise made in the structural design. The ideal form to carry the imposed loads enables the most economical design, in the sense that material weight, or volume, is minimum, as the size of every member is just enough to develop the allowable stress, and the process of finding the ideal form leads to, and remarkably, is also led by, clarity and deeper insights into the behavior of the structure. Emphasis had been paid on the importance of the ideal form since the time of Maxwell and Cremona, who harnessed the lucidity of geometry to study the problems of static equilibrium, through which developed the tools that helped the structural engineers in the coming times to build a variety of bridges, domes and towers – all without the help of computers. With the availability of immense computational resources at present, the problem of finding the optimum structural parameters for design – like, stiffness, weight or volume – has began to gain attention steadily.