Abstract
A design optimization problem for steel box girder sections is formulated and a numerical solution procedure is presented. The formulation is based on the load and resistance factor design (LRFD) procedure. The application of genetic algorithms (GAs) for a class of numerical examples is investigated. The steel box girder may have longitudinal stiffeners on flanges and webs and transverse intermediate stiffeners. Thus, the design variables may be continuous or discrete, which naturally makes the use of GAs attractive. Design constraints represent the LRFD versions of the Standard Specifications of Korean Highway Bridges. The dimensions of concrete slab and other appurtenance are assumed to be pre-determined and minimization of the unit weight of the steel box girder is taken as a design objective. As the numerical optimizers, the Internet version of simple GA (SGA) and micro-GA (μGA) are used and their performance and results are compared. In addition, the sequential quadratic programming algorithm is also applied for purposes of comparison. It is found that μGA with the population size of 5 is a suitable and reliable tool for the design optimization of steel box girder sections. The resulting design can be effectively used as an initial design for practical proportioning
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References
AASHTO (1998).AASHTO LRFD bridge design specifications, SI Units,Sécond Ed., AASHTO, Washington D.C.
Carroll, D. L. (1996). “Genetic algorithms and optimizing chemical oxygen-iodine lasers”.
Developments in Theoretical and Applied Mechanics, The University of Alabama, Vol. 18, pp. 411–424.
Carroll, D.L. (1998).FORTRAN Genetic algorithms (GA) driver, Dept. of Aeronautical and Astronautical
Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois.
Cho, H.N. and Jung, J.S. (1999). “Optimization of steel box girder bridges based on efficient reanalysis technique”.J. of Korean Society of Steel Construction, Vol. 11, No. 15, pp. 539–548.
Cho, H.N., Lee, D.H., Jung, J.S., and Min, D.H. (1999). “Reliability-based optimization of continuous steel box girder bridges.”J. of Korean Society of Civil Engineers, Vol. 19, No. I-3, pp. 397–406.
Goldberg, D. E. (1989).Genetic algorithm in search, optimization & machine learning, Addison-Wesley.
Holland, J.H. (1992).Adaptation in natural and artificial systems, A Bradford book, The MIT press.
IMSL (1998). FORTRAN77 math/library users manual, v3.01, IMSL Inc.
Jin, G.G. (2000).Genetic algorithms and their applications, Kyowoo-Sa, Seoul.
Krishnakumar, K. (1989), “Micro-genetic algorithms for stationary and non-stationary function optimization.”SPIE: Intelligent Control and Adaptive Systems, Vol. 1196, Philadelphia, PA.
MOCT (Korea Ministry of Construction & Transportation) (1996a).The standard specifications of Korean highwaybridges, KSCE, Seoul.
MOCT (1996b).The standard specifications of Korean highway bridges Appendix (LRFD), KSCE, Seoul.
MOCT (1997).Detailed design specifications of steel highway bridges, KSCE, Seoul.
Pezeshk, S, Camp, C.V., and Chen, D. (2000). “Design of nonlinear framed structures using genetic optimization.J. of Structural Engineering, ASCE, Vol. 126, No. 3, pp. 382–388.
Rajeev, S. and Krishnamoorthy, C. S. (1992). “Discrete optimization of structures using genetic algorithms”.J. of Structural Engineering, ASCE, Vol. 118, No. 5, pp. 1233–1250.
Rajeev, S. and Krishnamoorthy, C. S. (1997). “Genetic algorithms-based methodologies for design optimization of trusses”.J. of Structural Engineering, ASCE, Vol. 123, No. 3, pp. 350–358.
Ryu, Y.S., Kim, J.H., and Kim, J.T. (2001), “An application of genetic algorithms for the design optimization of composite steel box girder bridges”.Extended Abstracts of the Fourth World Congress of Structural and Multidisciplinary Optimization (WCSMO-4), June 4–8, 2001, Dalian, China, pp. 243.
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The manuscript for this paper was submitted for review on November 26, 2001.
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Ryu, YS., Kim, JH., Cho, HM. et al. LRFD-based design optimization of steel box girder sections using genetic algorithms. KSCE J Civ Eng 6, 127–134 (2002). https://doi.org/10.1007/BF02829129
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DOI: https://doi.org/10.1007/BF02829129