Cost optimization of flat and solid slabs reinforced concrete buildings using evolutionary algorithms under Eurocode

This study addresses cost optimization for multi-story reinforced concrete (RC) buildings, focusing on solid slabs (SS) and flat slabs (FS) subjected to gravity and lateral loads. An evolutionary algorithm is employed to minimize the total construction cost while adhering strictly to the strength and serviceability constraints defined by Eurocode 2 (EC2). A comparative study was conducted between the optimized designs and corresponding conventional Eurocode-based designs to quantify cost savings and differences in material use. Subsequently, a parametric analysis investigated a wide range of alternatives, including four concrete grades (25–40 MPa), five-column spacing options (3–7.5 m) and eight building heights (2–16 stories). Moreover, three-column configurations (rectangular, square and adaptive geometry) were analyzed. The results demonstrated the effectiveness of the proposed framework compared to conventional EC2-based designs, achieving total cost reductions of up to 10.34% for SS and 6.34% for FS. Rectangular columns consistently yielded lower construction costs, with savings up to 11.88% compared to square columns. However, square columns exhibited superior stability, proving preferable under high axial loads in buildings using lower concrete grades. The study confirms that integrating adaptive geometry selection enhances both structural integrity and cost-efficiency.