초록

○ 연구결과
국내 온실의 현황과 기상재해에 따른 피해양상에 대한 분석을 통하여 기존 온실의 문제점 및 개선방향을 제시하였으며 각종 보강방법대한 공학적 검토를 하였다. 그리고, 관련기관 등에서 쉽게 온실을 설계할 수 있는 시스템을 구축하였으며 기존 단순 유전자 알고리즘을 개선, 확장하여 단동 및 연동플라스틱온실 그리고 와이드 스팬형과 벤로형 유리온실의 구조해석과 단면 이산화 최적설계을 동시에 일괄적으로 수행 할 수 있는 통합시스템화 된 프로그램을 개발하였다.

Abstract ▼

Ⅳ. Results
The research results to develope optimum model and design systems for saving structural material and improving safety of greenhouse structure are summarized as follows;
1. Development of greenhouse model to reduce quantity of structural material required for construction and improve

Ⅳ. Results
The research results to develope optimum model and design systems for saving structural material and improving safety of greenhouse structure are summarized as follows;
1. Development of greenhouse model to reduce quantity of structural material required for construction and improve safety of greenhouse against meteorological damage.
1) Actual state of domestic greenhouse model types was investigated and analyzed, and structural safety for existing greenhouse was examined.
2) Structural safety was examined through analysis of structural characteristics of greenhouse by region and crop.
3) The greenhouse damage status and type by meteorological disaster was analyzed, and the cause of damage was examined by structural analysis.
4) It was proper that the constraint condition of foundation was 30cm underground fixed condition by experiment measuring displacements and breaking load for virtual wind and snow load acting on structure.
5) The experiment which acted unit wind and snow load on single-span greenhouse was conducted. By the results, maximum bending moment about each case of wind and snow load was different according to width, eave and roof height of greenhouse. Therefore, it was expected to be able to improve structural safety by optimizing width, eave and roof height of greenhouse.
2. Development of structural analysis program for greenhouse structure 1) The pre-processor and structural analyzer to be able to conduct structural analysis by inputting minimum data through constructing automatic input algorithm of data were developed.
2) The simple and cheap automatic greenhouse structural analysis program of GreenSAD(Greenhouse Structure Auto Design) was developed.
3) The first version of MAAS(Modeling and Analysis Program for Agricultural Structures) program to be able to conduct structural analysis for greenhouse and agricultural structures was developed.
4) Wind speed and snow depth according to return periods for design load estimation were calculated by frequency analysis using the weather data(maximum instantaneous wind speed, maximum wind speed, maximum depth of snow cover and fall) of 68 regions in Korea. Equations for estimating maximum instantaneous wind speed with maximum wind speed were developed for all, inland and seaside regions. The results were about the same as the current equation in general. Design wind speed and snow depth according to return periods were calculated and local design wind and snow load depending on return periods were presented together with iso-wind speed and iso-snow depth maps.
3. Development of optimum design system of greenhouse
For the optimum design, the objective function is the weight of structures and the constraints are limits on loads and serviceability. The basic search method for the optimum design is the genetic algorithm. The algorithm is known to be very efficient for the discrete optimization.
The genetic algorithms consists of genetic process and evolutionary process.
The genetic process selects the next design points based on the survivability of the current design points. The evolutionary process evaluates the survivability of the design points selected from the genetic process.
In the genetic process of the simple genetic algorithm, there are three basic operators: reproduction, cross-over, and mutation operators. To improve the efficiency of the simple genetic algorithm, this study shows that organization of size discrete optimization using improved simple genetic algorithms.
1) The objective of this study is the development of a size discrete optimum design algorithm for greenhouse structures, which is based on the genetic algorithm. The algorithm can perform section optimum designs of single and multi span greenhouse and wide-span, venlo glasshouse structures. The developed GA algorithm of greenhouse was implemented in a computer program.
2) Combining pre/post process, structural analysis and discrete optimum of member size into the genetic algorithms is what makes the practical discrete optimum design of complex single and multi span greenhouse and wide-span, venlo glasshouse structures possible.
3) The efficiency and validity of the developed discrete optimum design algorithm was verified by applying the algorithm to various optimum design examples:single and multi span greenhouse and wide-span, venlo glasshouse structures.
4) The result of the study indicates that the proposed optimal design program is more efficient than traditional design method currently used in practice.
4. The estimation of optimum greenhouse model and design system developed for reducing quantity of structural material required for construction and improving safety of greenhouse against meteorological damage.
1) The results analyzed by GreenSAD were same as the analysis results by commercial program currently used in practice.
2) Because input condition of program was simplified, the program could be utilized easily by user.
3) It was decided that the additional structural analysis was necessary for KSD3760(galvanized steel pipe) revised in 2006.
4) It was shown that the safety structural design each different greenhouse type could be conducted by using the developed formula and figure to be able to decide the frame interval of greenhouse.
5) It was shown that the economical efficiency and light environments of the optimum single-span greenhouse model developed in this study were excellent.
6) It was shown that the result designed by using the optimum design program developed in this study was more 11% - 25% profitable than the result designed by existing program.

목차 Contents

• 제출문 ... 1
• 요약문 ... 3
• SUMMARY ... 15
• CONTENTS ... 22
• 목차 ... 24
• 제1장 연구개발과제의 개요 ... 27
• 제1절 연구개발의 목적 및 필요성 ... 27
• 제2절 연구개발의 내용 및 범위 ... 30
• 제2장 국내외 기술개발 현황 ... 33
• 제3장 연구개발수행 내용 및 결과 ... 36
• 제1절 기존 온실의 개선 및 최적모델개발 ... 36
• 1. 국내 온실 현황 ... 36
• 2. 농업시설의 기상재해 현황 ... 37
• 3. 원예시설의 기상재해 사례 및 피해 양상 ... 39
• 4. 설계하중 ... 49
• 5. 국내 단동온실의 구조 현황 ... 54
• 6. 지역별, 재배작물별 온실구조의 특성 ... 63
• 7. 농가지도형 비닐하우스의 구조안전성 ... 67
• 8. 온실의 구조에 따른 안전성 분석 ... 70
• 9. 단동비닐하우스의 설해 경감을 위한 보강방법 개발 ... 83
• 10. 보강방법별 한계하중 실험 ... 93
• 11. 기존 온실모델에 있어서 구조적 보완사항 분석 ... 95
• 12. 단동온실의 간이 설계방법 개발 ... 109
• 제2절 온실용 구조해석 프로그램 개발 ... 129
• 1. 온실 설계용 기상자료 분석 ... 129
• 2. 온실의 하중 재하시험 ... 173
• 3. CFD를 이용한 풍력계수 산정 ... 186
• 제3절 온실의 자재절감 및 안전성 향상을 위한 최적설계시스템 개발 ... 197
• 1. 온실구조설계에 최적화 기법 도입 타당성 검토 ... 197
• 2. 최적설계기법 ... 203
• 3. 이산최적설계프로그램 개발 ... 233
• 4. 온실구조물의 최적설계 예 및 결과고찰 ... 239
• 5. 결론 ... 276
• 제4절 온실의 자재절감 및 안전성 향상을 위한 최적 모델 및 설계시스템 평가 ... 277
• 1. 온실 설계용 프로그램의 평가 ... 277
• 2. 온실 최적설계자료의 사용성 및 현장 적용 방안 ... 281
• 3. 온실의 자재절감 및 안전성 향상을 위한 최적모델 평가 ... 282
• 제5절 결론 ... 283
• 제4장 목표달성도 및 관련분야에의 기여도 ... 289
• 제1절 연구개발 목표달성도 ... 289
• 제2절 관련분야 기술발전에의 기여도 ... 289
• 제5장 연구개발 결과의 활용 계획 ... 291
• 제6장 연구개발과정에서 수집한 해외과학기술정보 ... 293
• 1. 외국의 온실 구조설계기준 현황 ... 293
• 2. 수집 해외과학기술정보 ... 294
• 제7장 참고문헌 ... 295
• 부록 ... 300
• <부록1> 온실모델별 서까래 간격별 한계적설심 ... 301
• <부록2> 온실모델별 서까래 간격별 한계풍속(평균지붕높이 풍속 고려) ... 342
• 끝페이지 ... 423