TOPOLOGY OPTIMIZATION OF TRUSS STRUCTURE BASED ON OVERLAPPING-FILTER AND STABILITY CONSTRAINTS

Considering the manufacture and assemble techniques, overlap elements should be avoided in structure design in practical engineering. In truss topology optimization using the ground structure method, overlap elements are abandoned under a given set of chosen nodal points, which may lead to un-optimum designs. Adding or deleting element in the topology result is of no warranty; meanwhile, it’s unreasonable if the overlap elements are reserved. This paper presents an accurate mathematical description of overlapping with more elements included in the initial ground structure. The Heaviside function is used to map the element cross-sectional area with the property of intersection to get the sensitivity information. Overlapping-filter constraints and fundamental eigenvalue constraint are imposed in the optimization model. Local stability constraints are imposed in order to prevent unstable result. Overlapping-phenomenon is avoided by the formulation of the topology optimization. Finally the method was applied to two examples to testify the validity of the proposed method and obtain a more reasonable result for actual projects.