View - Universidad de Almería

Proceedings of GO 2005, pp. 77 – 80.Reliable Optimization in Civil Engineering— Structural and Numerical Optimizationof Civil Engineering Problems ∗András Erik Csallner, 1 Tibor Csendes, 1 and András Balázs Kocsis 21 University of Szeged, Szeged, Hungary, csallner@jgytf.u-szeged.hu2 KÉSZ Ltd., Szeged, HungaryAbstractKeywords:It is shown in this work, how engineering problems, especially some kinds of civil engineering problemscan be solved using verified techniques exploiting the knowledge of structure and engineers’habits. Some numerical results are also mentioned.Civil engineering, patents, reliable methods.1. IntroductionCivil engineering is a field — as many of other engineering sciences (e.g. see [1]) — wherethe most of methods used for solving optimization problems are based on experience andexperiments, and models using local information, however drawn from global models [6].The present work outlines interesting classes of problems from this field, and initiates somepossible ways to solve those problems utilizing the wide tool capabilities of interval arithmeticfor error handling and interval branch-and-bound algorithms [4, 5, 7, 8] to solve the originalor modified industrial models automating civil engineers’ work. The investigations are in anearly stage but are promising both in a theoretical and in a practical sense. The final aim is tocontribute to the refinement of emerging industrial standards and patents such as [9–12].Reliable numerical techniques have substantial advantages and a bright future in civil engineeringcomputational procedures, still there is a long way to go. The talk highlights a simpleexample problem with the traditional engineering solution and with the interval arithmeticbased result of tolerance optimization. We report on the solution and numerical experiencescollected investigating civil engineering design problems. A subsequent careful study mustclear the consequences and advantages of such approaches with special attention to the relatedapplication fields.2. A Simple ProblemThe problems arising in civil engineering are MINLP problems. The integer part describes thedecision of different materials and properties which are scaled (e.g. the thickness of differentenforcement steel bars), whilst the nonlinear part realizes the physical model in most of thecases.∗ This work was supported by the KÉSZ Ltd. (www.kesz.hu), and by the Grants OTKA T 048377, and T 046822.