In concrete structures, rebar waste is included in rebar costs. For a concrete element, the rebar design process involves determining the required steel using mandatory codes and estimating the number of rebars that must be placed. In real-world and large-scale instances, designing a layout without accounting for waste generated during the cutting process results in substantial expenditures for the purchase of rebar. Moreover, inefficient cutting patterns contribute to waste generation. To address this, this paper jointly optimizes the cutting plan and rebar layout possessing heterogeneous rebars for a set of concrete elements to satisfy the determined area of steel and minimize total reinforcement cost. Since the high level of heterogeneity in the rebar layout leads to a complicated plan from a practical point of view, the suggested approach provides the most cost-effective arrangement of rebar based on the customer-specified maximum heterogeneity. The proposed model for large-scale problems is computationally intractable, so a Column-Generation based approach is developed to solve the proposed model. Finally, the model is tested using a real-world case including 145 concrete beams. These experiments confirmed that the analytical framework could iteratively identify the efficient cutting patterns as well as the layout design that result in a significant decrease in total purchased rebar and consequently rebar waste in each iteration.

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