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Quasi-Static Structural Optimization Technique Using Equivalent Static Loads Calculated at Every Time Step as a Multiple Loading Condition

매 시간단계의 등가정하중을 다중하중조건으로 이용한 준정적 구조최적화 방법

  • Published : 2000.10.01

Abstract

This paper presents a quasi-static optimization technique for elastic structures under dynamic loads. An equivalent static load (ESL) set is defined as a static load set which generates the same displacement field as that from a dynamic load at a certain time. Multiple ESL sets calculated at every time step are employed to represent the various states of the structure under the dynamic load. They can cover every critical state that might happen at an arbitrary time. Continuous characteristics of dynamic load are simulated by multiple discontinuous ones of static loads. The calculated sets of ESLs are applied as a multiple loading condition in the optimization process. A design cycle is defined as a circulated process between an analysis domain and a design domain. Design cycles are repeated until a design converges. The analysis domain gives a loading condition necessary for the design domain. The design domain gives a new updated design to be verified by the analysis domain in the next design cycle. This iterative process is quite similar to that of the multidisciplinary optimization technique. Even though the global convergence cannot be guaranteed, the proposed technique makes it possible to optimize the structures under dynamic loads. It has also applicability, flexibility, and reliability.

Keywords

Equivalent Static Load;Multiple Loading Condition;Design Cycle;Analysis Domain;Design Domain;Time Step

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