DESIGN OPTIMIZATION OF RECTANGULAR RC BEAMS USING GENETIC ALGORITHM

Abstract

The study presents an optimal design of simply supported rectangular reinforced concrete beams based on the ultimate limit state philosophy of BS8110 and using genetic algorithm as optimization tool. An optimization model was formulated. The model consists of an objective function which focuses on minimizing the steel ratio of the beams and constraint equations which are focused on checking that all the requirements of BS8110 for the design of reinforced concrete beams are satisfied. Results obtained showed a difference of up to 46% and 12.6% in steel ratios obtained using the traditional approach and those obtained using the optimization model for singly and doubly reinforced concrete beams respectively, depending on the magnitude of the applied moment. The model has proved to minimize the final dimensions of rectangular reinforced concrete beams and by implication, the steel ratio even though all the requirements of the code were satisfied.

Keywords

• Optimization
• Rectangular beams
• reinforcement ratio
• genetic algorithm

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