Topology Optimization Of Cylindrical Reticulated Shell Based On Parametric Modeling

Shell structure as a kind of large space structures, are widely used in the landmark building structure in recent years, because of its advantages such as reasonable force, economic use of materials, beautiful shape, larger span, and so on. However, a large number of practice proved, traditional design can only guarantee the safety, usability and durability of structure, but can not brought the mechanical properties into full play, we need to do optimization of the structure, in order to use the material properties more rational, and make each unit within the structure better coordination.This paper is in-depth study of the basic theory, algorithm improvement and procedures of the sequential two-level algorithm and genetic algorithm, for the present structural optimization theory and various optimization algorithms, and on this basis to achieve the section optimization design of the single-layer cylindrical reticulated shell and the topology optimization design of the double-layer cylindrical reticulated shell.The main content of the paper is as followed:(1) The section optimization of the five typical single-layer cylindrical shell is carried out used the sequential two-level algorithm. The constraints are divided into two kinds, they are the local constraints and whole constraints, and the one-dimensional search algorithm and the relative difference quotient algorithm are adopted corresponding to the two kinds constraints. It is analyzed detailed how the total weight of bars changes while the span, rise to span changes dependently. It is compared that which scheme is the best on the six commonly used in project span and the six rise to span.(2) In this paper, encoding using integer coding, crossover and mutation using hybrid crossover and local search on the study of the basic genetic algorithm. The topology optimization of square pyramid double-layer cylindrical shell using the improved genetic algorithm is realized. It is analyzed detailed how the total weight of bars changes while the rise to length, rise to span and thickness changes dependently under the 50m span of the square pyramid cylindrical shell. It is compared that which rise to span and thickness is the best on this paper mesh shares.(3) Cylindrical reticulated shell is carried out the analysis by the software ANSYS, and modeling parameters used the language of the APDL. Optimization procedure is programmed by the MATLAB, and data transfers between MATLAB and ANSYS by the reading and writing file.