Paper ID : 6790

Prestressed Concrete I-Girder Optimization
via Genetic Algorithm

Tito Adibaskoro1and Made Suarjana2

1Former Student, Faculty of Civil and Environmental Engineering, Institut Teknologi Bandung, Bandung 40132, Indonesia

2Associate Professor, Faculty of Civil and Environmental Engineering, Institut Teknologi Bandung, Bandung 40132, Indonesia





Prestressed concrete has been gaining popularity in the construction industry because of its many advantages, including reduced dead load due to less material used and overall cost saving. Nonetheless, a single prestressed concrete I-girder as a structural element in highway bridges is still significantly costly and massive, thus optimization can yield a significant amount of saving as well as reduced material consumption. In this paper, prestressed concrete I-girder optimization is carried out by implementing genetic algorithm (GA), a method inspired by nature’s evolution and natural selection. This study evaluates many aspects of genetic algorithm applied for optimizing material cost of prestressed concrete I-girder design. A new method for calculating fitness value is proposed, which is proven to be essential for the application in this study. As the result of the optimization process, the best solution is presented, defined by being the least costly solution while still maintaining compliance with AASHTO LRFD 2007 design code, including ultimate strength, service stresses and deflection, detailing requirements, geometrical feasibility, etc. Lastly, sensitivity analysis is carried out, discussing the influence of starting conditions to the output of the optimization process.

Keywords:  Genetic algorithm; Highway bridges; I-girder; Optimization; Prestressed concrete.



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ISSN: 2338-5502