Design of Reinforce Transfer Beam with Topology Optimization Method by a Spread-over Reinforcement Model

Abstract

This research presents an analytical study aimed at optimizing the design efficiency of reinforced concrete transfer beams using a spread-over reinforcement modeling approach in topology optimization. The case study involves a 12-story hospital building with one basement level, where the primary load-bearing system consists of columns and shear walls supporting both vertical and lateral loads. The transfer beam has a span length of 6.80 meters, a depth of 1.70 meters, classifying it as a deep beam, and is subjected to a load of 351.9 tons with an eccentric column load. The analysis employs an evolutionary structural optimization process using MATLAB to determine the optimal shape under material cost constraints, considering the combined cost of concrete and reinforcement steel. The results indicate that in the 36th iteration, the optimized topology yields a total material cost of 188,050.91 THB. This was then compared with a beam designed according to ACI 318-19 standards. The findings reveal that the proposed optimization approach produces a structural form closely resembling the Strut-and-Tie Model, leading to a 62.53% reduction in concrete volume while maintaining permissible deflection and stress levels. This approach enhances structural design efficiency while minimizing environmental impact.