YU Y Q, HAN W Z, WANG C. Topology optimization design of castable cross-plate joints [J]. Journal of Henan Polytechnic University (Natural Science) , 2025, 44(4): 170-178.

doi: 10.16186/j.cnki.1673-9787.2023110038

Received: 2023/11/17

Revised: 2024/03/04

Published: 2025/06/19

Topology optimization design of castable cross-plate joints

Yu Yongqiang1, Han Wenzhe1, Wang Chao2

1.School of Civil Engineering， Henan Polytechnic University， Jiaozuo  454000， Henan， China；2.School of Civil Engineering and Architecture， Henan University， Kaifeng  475000， Henan， China

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 introduces 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 structural 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 employed. 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 demonstrate that integrating casting constraints into the optimization process effectively addresses the casting challenges associated with conventional methods. Variations in demoulding direction and material volume significantly 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 practical guidance for the castability-aware design of cast-steel joints in spatial structures. 

Key words: topology optimization; cross-plate joint; castability; cast-steel joint; spatial structure