Topology optimization design of castable cross-plate joints

Yu Yongqiang; Han Wenzhe; Wang Chao

doi:10.16186/j.cnki.1673-9787.2023110038

Abstract：Objectives Cross-plate joints are widely used in spatial structures.However,traditional topology optimization methods often produce geometrically complex results that are difficult to cast.This study intro-duces a topology optimization approach that incorporates casting constraints to improve the castability of such joints.Methods A density-based topology optimization framework is adopted,aiming to minimize struc-tural compliance(i.e.,maximize stiffness)while considering both material volume and casting constraints.To mitigate intermediate density issues,a combination of density filtering and threshold projection is em-ployed.The P-norm function is introduced to address the differentiability of the casting constraint function.Optimization designs are conducted for typical 2D and 3D cross-plate joints.Results The results demon-strate that integrating casting constraints into the optimization process effectively addresses the casting chal-lenges associated with conventional methods.Variations in demoulding direction and material volume signifi-cantly influence joint design-appropriate demoulding directions and sufficient material availability lead to high-performance outcomes.Additionally,filter radius and mesh density affect design quality:smaller filter radii yield finer designs,and denser meshes result in smoother configurations.Conclusions The proposed method produces innovative joint configurations that satisfy castability requirements.This work offers practi-cal guidance for the castability-aware design of cast-steel joints in spatial structures.