표제지
목차
제1장 서론 9
1.1. 연구 배경과 목적 9
1.2. 연구 범위와 내용 11
1.3. 논문의 구성 12
제2장 기존 연구 및 이론 고찰 13
2.1. 기존 연구 동향 13
2.1.1. 콘크리트 충전 강관에 관한 연구 13
2.1.2. 콘크리트 비충전 강관에 관한 연구 14
2.1.3. 고유진동수 및 동적 특성에 관한 연구 15
2.2. 설계 기준 16
2.2.1. 해양구조물 설계 기준 16
2.2.2. API RP 2A 설계 기준 17
2.3. 적용 하중 이론 및 해석 이론 18
2.3.1. 초기 응력과 고유진동수에 관한 기존 연구 고찰 18
2.3.2. DNV GL 환경하중 이론 20
2.3.3. 풍 하중(Wind Load) 21
2.3.4. 파 하중(Wave Load) 23
2.3.5. 조류 하중(Current Load) 25
2.3.6. 부가 질량(Added Mass) 27
2.3.7. 풍력 터빈 중력 하중(Wind Turbine Gravity) 28
2.4. 모달 해석 이론 30
제3장 파일-레그 연결방식에 대한 해석 조건 32
3.1. 해석 모델의 선정 32
3.1.1. 콘크리트 충전 연결 방식 모델 33
3.1.2. 콘크리트 비충전 연결 방식 모델 34
3.1.3. 경사형 콘크리트 비충전 연결 방식 모델 35
3.2. 모델 제원 및 재료의 특성 36
3.3. 하중 조건 38
3.4. 경계 조건 40
제4장 파일-레그 연결방식에 대한 해석 결과 41
4.1. 파일-레그 연결 방식과 형상의 고유진동수 분석 결과 41
4.1.1. 콘크리트 충전 자켓 구조물 해석 결과 42
4.1.2. 콘크리트 비충전 자켓 구조물 해석 결과 48
4.1.3. 경사형 콘크리트 비충전 자켓 구조물 해석 결과 54
4.2. 파일-레그 연결 방식과 형상에 대한 공진 안전성 결과 60
제5장 결론 63
5.1. 결론 63
5.2. 추후연구 65
참고문헌 66
국문초록 70
Abstract 72
List of Tablse
Table 2.1. Design Criteria for Offshore and Jacket Structures 16
Table 2.2. Specification for NREL-5MW Wind Turbine 28
Table 3.1. Connection and Shape Type of Jacket Structures 32
Table 3.2. Specification for Analysis Model Types 36
Table 3.3. Main Tubular Section Size for Analysis Models 36
Table 3.4. Material Constants for Steel 37
Table 3.5. Material Constants for Concrete Grout 37
Table 3.6. External Load and Added Mass Conditions for Analysis 38
Table 3.7. NREL-5MW Wind Turbine Gravity Load and Added Mass... 39
Table 4.1. Summary of 1st Natural Frequency[Hz] for Analysis Results 41
Table 4.2. Natural Frequency[Hz] for Grouted Connection 46
Table 4.3. Natural Frequency[Hz] for Non-Grouted Connection 52
Table 4.4. Natural Frequency[Hz] for Sloped Non-Grouted Connection 58
Table 4.5. Natural Frequency[Hz] for Analysis Models in NREL-5MW... 61
Fig. 1.1. Offshore Wind Turbine Foundations 9
Fig. 2.1. Terminology and Geometric Parameters, Simple Tubular... 17
Fig. 2.2. General Environment Loads of Jacket Structures 20
Fig. 2.3. Ocean Wave Theory 23
Fig. 2.4. Frequency Ranges of Wind Turbine and Wave for avoiding... 29
Fig. 3.1. Analysis Model for Grouted Connection 33
Fig. 3.2. Analysis Model for Non- Grouted Connection 34
Fig. 3.3. Analysis Model for Sloped Non- Grouted Connection 35
Fig. 3.4. Boundary Condition for Analysis Model 40
Fig. 4.1. Natural Frequency and Mode Shape (1st~4th) for Grouted Connection in No External Load and No Added Mass Condition 42
Fig. 4.2. Natural Frequency and Mode Shape (1st~4th) for Grouted Connection in External Load and No Added Mass Condition 43
Fig. 4.3. Natural Frequency and Mode Shape (1st~4th) for Grouted Connection in No External Load and Added Mass Condition 44
Fig. 4.4. Natural Frequency and Mode Shape (1st~4th) for Grouted Connection in External Load and Added Mass Condition 45
Fig. 4.5. Natural Frequency Variation of Grouted Connection by Modes... 47
Fig. 4.6. Natural Frequency and Mode Shape (1st~4th) for Non-Grouted Connection in No External Load and No Added Mass Condition 48
Fig. 4.7. Natural Frequency and Mode Shape (1st~4th) for Non-Grouted Connection in External Load and No Added Mass Condition 49
Fig. 4.8. Natural Frequency and Mode Shape (1st~4th) for Non-Grouted Connection in No External Load and Added Mass Condition 50
Fig. 4.9. Natural Frequency and Mode Shape (1st~4th) for Non-Grouted Connection in External Load and Added Mass Condition 51
Fig. 4.10. Natural Frequency Variation of Non-Grouted Connection by... 53
Fig. 4.11. Natural Frequency and Mode Shape (1st~4th) for Sloped Non-Grouted Connection in No External Load and No Added Mass Condition 54
Fig. 4.12. Natural Frequency and Mode Shape (1st~4th) for Sloped Non-Grouted Connection in External Load and No Added Mass Condition 55
Fig. 4.13. Natural Frequency and Mode Shape (1st~4th) for Sloped Non-Grouted Connection in No External Load and Added Mass Condition 56
Fig. 4.14. Natural Frequency and Mode Shape (1st~4th) for Sloped Non- Grouted Connection in External Load and Added Mass Condition 57
Fig. 4.15. Natural Frequency Variation of Sloped Non-Grouted... 59
Fig. 4.16. Natural Frequency Ranges for Analysis Models in NREL-5MW... 62