Parameter And Location Optimization Of Dampers In Building Structural Systems Based On Improved Artificial Fish Swarm Algorithm

With the continuous development of damping technology,the placement of dampers in building structures has become an effective means to enhance structural seismic performance and protect the safety of main structures.However,due to the influence of human factors on different damper placement schemes and parameter settings which lack theoretical support,it is difficult to determine the optimal placement scheme and parameter settings.In this study,a framework for optimizing the placement of Viscous Dampers（VD）in framed structures was proposed based on the Basic Artificial Fish Swarm Algorithm（BAFSA）combined with finite element software SAP2000.The model can simultaneously optimize the placement and parameters of VD in multi-dimensional and multi-degree-of-freedom actual finite element structural models.By optimizing the placement scheme of VD in an actual structure and comparing it with the preliminary placement scheme,the results show that the optimization model proposed in this paper can effectively improve the seismic performance of the structure.The main contents and research results of this paper include:（1）This research focuses on a five-story reinforced concrete frame structure located in a high-intensity seismic area with a design intensity of 0.15g in a certain earthquake-prone region of Honghe Prefecture,Yunnan Province.To mitigate earthquake damage,a Viscous Damper（VD）was adopted for the structure,and the parameters and locations of the VD were optimized using the Artificial Fish Swarm Algorithm（AFSA）,resulting in both the preliminary and the AFSA-optimized layout schemes.The calculation results indicate that the optimized structural system meets the expected additional damping ratio of the project and satisfies the requirements of the"Technical Points for Seismic Design Review of Building Engineering in Yunnan Province"（Trial）,meaning it can maintain the expected additional damping ratio even after 0.1 times U₀.（2）BAFSA includes four behaviors:foraging,swarming,chasing,and random behavior.Based on the damper placement scheme and parameters,an improved BAFSA algorithm was established.By comparing the data of the structural system with the preliminary placement scheme,the results show that the placement scheme optimized by the improved BAFSA algorithm is better than the structural system of the preliminary placement scheme in terms of inter-story displacement angle,floor shear force,damping rate,and vertex displacement time history curve under rare earthquakes.（3）This study aims to use an optimized objective function to enable BAFSA to effectively evaluate the seismic performance of the structure after placing VD dampers.By comparing the results before and after optimization,it can be found that the key factors affecting the structural system,such as inter-story shear force,inter-story displacement,inter-story displacement angle,and additional damping ratio,are significantly reduced when the objective function is optimized.This indicates that the placement scheme optimized by the improved BAFSA algorithm is feasible.