Method And Its Application Research On Topology Optimization Designs Of Bridge Structures

Structural topology optimization has been treated as one of the most challenging tasks in structural optimization design, and is an innovative approach. For the problem of topology optimization designs of continuum structures, this thesis summarizes and analyzes the present status and the development of Evolutionary Structural Optimization method.Generally speaking, bridge structures are subjected to the dead load(structural weight)and the live load(automobile load etc.). The dead load is a design-relative load. When the space occupied by the initial design structure is much larger than the space occupied by the optimum bridge structure, the effect of the dead load is more and more important than the effect of the live load on structural optimization designs. In order to make sure that the optimum design structure is of reasonable transferring live load path, and enforce the effect of the live load on structural optimization designs, the live load is replaced by an efficiency live load in this thesis. Then, this thesis proposes a new evolutionary structural optimization method dealing with multiple load cases, multiple constrains, the dead load and the live load. And this thesis gives a set of algorithm of the evolutionary structural optimization method considering stress and displacement requirements and multiple load cases, and a set of algorithm of the evolutionary structural optimization method considering stress and strain energy requirements and multiple load cases. Moreover, this thesis makes researches on the loading way of steel cable pre-stressed of cable-stayed bridges, and proposes a spatial bridge structural topological optimization method with multiple load cases and multiple load cases and multiple constraints.For the mentioned-above proposed methods the procedures are implemented, and some simulation examples dealing with bridges are given. Results obtained show that the proposed methods in this thesis are correct and efficient, and are of good engineering application value.