This study was conducted to find out the best optimum design method for the design of reinforced concrete agricultural aqueduct abutment and pier structures. The mixed-discrete optimization and continuous optimization method were applied to the design of reinforced concrete agricultural aqueduct abutment and pier and the results of these optimization methods were compared each other. It is proved that mixed-discrete optimization method is more reliable, efficient and reasonable than continuous optimization method for the optimum design of the reinforced concrete agricultural aqueduct abutment and pier.

Optimum Design of Reinforced Concrete Agricultural Aqueduct Abutment and Pier Using Continuous and Mixed-Discrete Optimization Methods

This study was conducted to find out the best optimum design method for the design of reinforced concrete agricultural aqueduct abutment and pier structures. The mixed-discrete optimization and continuous optimization method were applied to the design of reinforced concrete agricultural aqueduct abutment and pier and the results of these optimization methods were compared each other.It is proved that mixed-discrete optimization method is more reliable, efficient and reasonable than continuous optimization method for the optimum design of the reinforced concrete agricultural aqueduct abutment and pier. Keywords: Continuous optimization method; mixed-discrete optimization method; reinforced concrete agricultural aqueduct I. 서 론 * 최적설계란 주어진 제약조건을 만족시키면서 목적함수의 값이 최대 또는 최소가 되도록 설계변수 값을 결정하는 과정이다. 구조물의 최적설계시 목적함수는 건설비용이나 구조물의 중량 등이 되며, 제약조건으로는 변위제약과 응력제약 등이 고려된다 (Jung 등, 1997). 철근콘크리트 구조물의 최적설계에서는 콘크리트의 강도, 구조물의 형상, 콘크리트 단면 치수, 콘크리트 단면내의 철근량 등이 설계변수로 적용된다. 일반적으로 철근콘크리트 구조물의 설계시 콘크리트 강도와 철근량 등은 미리 규격화된 값 (이산자료) 중에서 선택되며, 콘크리트 단면치수는 규격화된 값을 적용하는 것이 아니라 일반적으로 경험시 적용하는 단면을 선택하여 설계에 적용하고 있다 (Jung 등, 1997). 이산형 최적설계기법 연구로는 Jung 등 (1997)의 변수분리의 원리에 의한 철근콘크리트 평면 뼈대 구조물의 최적화기법, Cella 등 (1971)의 Combinatorial Algorithm 에 의한 방법, Reinschmidt 등에 의한 묵시적 열거법, Lai 등 (1973)에 의한 Hooke and Jeeves의 Pattern Search 등을 확장한 최적화기법이 있다. Choi

Weight minimization for the steel bridge girders using an approximation based optimization technique is presented. To accomplish this, an optimization oriented finite element program is used to achieve continuous weight reduction until the optimum is reached. To reduce computational cost, approximation techniques are adopted during the optimization process. Constraint deletion as well as intermediate design variables and responses are also used for higher qualitv of approximations and for a better convergence rate. Both the reliability and the effectiveness of the underlying optimization method are reviewed.

Yearn-Tzuo(Andrew)

Papers

Minimum Weight Design for Bridge Girder using Approximation based Optimization Method