en Structure-Concrete Structure- Concrete Research Paper Research Paper <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">This article presents the application of two algorithms: heuristic big bang-big crunch (HBB-BC) and a heuristic particle swarm</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">ant colony optimization (HPSACO) to discrete optimization of reinforced concrete planar frames subject to combinations of</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">gravity and lateral loads based on ACI 318-08 code. The objective function is the total cost of the frame which includes the cost</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">of concrete, formwork and reinforcing steel for all members of the frame. The heuristic big bang-big crunch (HBB-BC) is based</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">on BB-BC and a harmony search (HS) scheme to deal with the variable constraints. The HPSACO algorithm is a combination of</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">particle swarm with passive congregation (PSOPC), ant colony optimization (ACO), and harmony search scheme (HS)</font></font></i></p> <p align="LEFT"><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">algorithms. In this paper, by using the capacity of BB-BC in ACO stage of HPSACO, its performance is improved. Some design</font></font></i></p> <p><i><font face="Times New Roman" size="2"><font face="Times New Roman" size="2">examples are tested using these methods and the results are compared.</font></font></i></p> Structural optimization, Reinforced concrete plane frames, Big Bang-Big Crunch algorithm, Particle swarm, Ant colony optimization 193 206 http://ijce.iust.ac.ir/browse.php?a_code=A-10-218-5&slc_lang=en&sid=1 Ali Kaveh alikaveh@iust.ac.ir 1800319475328460010191 1800319475328460010191 Yes Iran University of Science and Technology Omid Sabzi 1800319475328460010192 1800319475328460010192 No Iran University of Science and Technology