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In this paper, the optimum design of a reinforced concrete one-way ribbed slab, is presented via recently developed metaheuristic algorithm, namely, the Mouth Brooding Fish (MBF). Meta-heuristics based on evolutionary computation and swarm intelligence are outstanding examples of nature-inspired solution techniques. The MBF algorithm simulates the symbiotic interaction strategies adopted by organisms to survive and propagate in the ecosystem. This algorithm uses the movement, dispersion and protection behavior of Mouth Brooding Fish as a pattern to find the best possible answer. The cost of the system is considered to be the objective function, and the design is based on the American Concrete Institute’s ACI 318-08 standard. The performance of this algorithm is compared with harmony search (HS), colliding bodies optimization (CBO), particle swarm optimization (PSO), democratic particle swarm optimization (DPSO), charged system search (CSS) and enhanced charged system search (ECSS). The numerical results demonstrate that the MBF algorithm is able to construct very promising results and has merits in solving challenging optimization problems.

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This study presents a cost optimization approach for simply supported one-way ribbed slabs, with the primary objective of minimizing concrete and reinforcement costs. A Genetic Algorithm (GA), implemented in MATLAB, is utilized to address this optimization problem. The optimization model incorporates seven discrete design variables: rib dimensions (spacing, bottom/top width, and height), topping slab thickness, flexural reinforcement diameter, and concrete compressive strength. For validation, an initial optimization based on ACI 318-08 with six variables demonstrated a 3% cost reduction compared to established algorithms. To ensure practical relevance, subsequent optimizations incorporated actual market conditions utilizing the 2025 Iranian Building Construction Price List. Transitioning to ACI 318-19 resulted in a 10% increase in optimal cost relative to ACI 318-08, primarily due to stricter shear strength provisions. To mitigate this increase and enhance design efficiency, concrete compressive strength was introduced as a seventh design variable. This expanded optimization was evaluated across spans ranging from 5 to 8 meters, yielding a further 4.4% cost reduction for a 6-meter span. Conclusively, the results demonstrate that the strategic application of higher-strength concrete, informed by real-world market prices, significantly reduces the overall cost of one-way ribbed slab construction.