空間トラス構造物の耐力評価法: Compact Procedure Methodを用いた多目的最適化

摘要

With the rapid development of computer technology, it has become reality for high speed calculation to be applied in the field of structural optimization. Now computer calculation is applied throughout the field for practical optimal design like cost optimization. These applications might result in structural designs that lack redundancy and residual performance. In order to ensure structural safety, it is necessary to estimate structural responses caused by unexpected external disturbances. In this study, structural residual performance is considered as a method of judging structural redundancy. It is widely acknowledged that ensuring structural redundancy is vital for structural safety. But the question is that it is still difficult to quantify the redundancy itself. As a method to quantify structural redundancy, compact procedure method to calculate ultimate bearing capacity of rigid frame structures was proposed by Livesley in 1976. Through lower-bound theorem in limit analysis and linear programming, compact procedure method was adopted for structural calculation. This method is essentially the same as simplex method, only more convenient with no slack variables required. Furthermore, the application of this method from frame structures into space truss structures has also been successful. Combining compact procedure method with a multi-objective optimization algorithm, Strength Pareto Evolutionary Algorithm 2 (SPEA2), taking space truss structure as analysis object, we propose a multi-objective structural optimization of space truss structures in this paper.%高速演算を可能とするコンピュータの発達により，従来，計算負荷が大きく実用的見地から重要視されてこなかった構造最適化手法が見直され，実設計への応用も次第に広がりつつある。