표제지
Abstract
요약
목차
제1장 서론 12
1.1. 연구목적 12
1.2. 연구동향 13
1.3. 연구의 방법 및 구성 14
제2장 사장교의 해석방법 15
2.1. 최종 구조시스템의 고정하중 모멘트 15
2.2. 최종 케이블 장력 18
2.3. 예비설계시의 부재 제원 21
2.3.1. 거더 21
2.3.2. 케이블 22
2.4. 온도의 영향 24
제3장 사장교 가설 중 구조의 비선형성 25
3.1. 카테나리 곡선과 포물선의 비교 25
3.2. 등가탄성계수 29
3.2.1. Secant계수 29
3.2.2. Tangent계수 31
3.3. 등가탄성계수의 중요성 32
3.4. Nonlinear Construction Analysis 37
3.4.1. Secant vs. Tangent Modulus for Single degree of freedom systems 37
제4장 전진법(순방향 해석) 39
4.1. 일반화된 매트릭스 식 39
4.1.1. P-n 매트릭스(이미지참조) 40
4.1.2. CG- 매트릭스(이미지참조) 41
4.1.3. K= 매트릭스(이미지참조) 42
4.1.4. Y-n 매트릭스 → Y-n ; initial cable force unknown(이미지참조) 42
4.2. 매트릭스식의 수 43
4.3. 가설단계의 변동 46
4.4. 비선형 해석 46
제5장 후진법(역방향 해석) 47
5.1. 일반식 47
5.2. 주경간 및 측경간의 해석 47
5.3. 자료의 정리 53
5.3.1. Flow chart of Computer Files 53
5.3.2. 가설단계의 변동 54
5.4. 비선형 해석 55
제6장 전진법과 후진법의 비교 57
6.1. 전진법과 후진법의 비교 57
6.1.1. 전진법(순방향 해석) 57
6.1.2. 후진법(역방향 해석) 58
제7장 수치 예 60
7.1. 전진법(순방향 해석) 61
7.2. 후진법(역방향 해석) 67
제8장 결론 76
참고문헌 77
부록 : MIDAS 해석 79
Table 4.1. Individual bridge actions and superposition 45
Table 4.2. Superposition of individual bridge actions 45
Table 7.1. Mechanical properties of bridge members 60
Table 7.2. Sectional properties of bridge members 61
Table 7.3. Comparison of cross sectional areas of cables 65
Table 7.4. Comparison of initial forces by the forward Method and the Backwards Method 72
Figure 2.1. Desirable dead load moment distribution 15
Figure 2.2. N-Mz relationship for typical girder cross section.(이미지참조) 16
Figure 2.3. Comparison of actual and allowable girder moments for initial dead load moment distribution. 17
Figure 2.4. Favorable dead load moment distribution. 17
Figure 2.5. Comparison of actual and allowable girder moments for second dead load moment distribution 18
Figure 2.6. Horizontal girder system 18
Figure 2.7. Curved girder 19
Figure 2.8. Unbalanced tower forces 20
Figure 2.9. Balanced tower forces 21
Figure 2.10. Axial force of girderr 22
Figure 2.11. Cable sectional area for radiating geometry 23
Figure 2.12. Cable sectional area for harp geometry 23
Figure 3.1. Cable geometry 25
Figure 3.2. Cable subject to change of tension 26
Figure 3.3. Differences of cable length 27
Figure 3.4. Horizontal cable geometry 27
Figure 3.5. Catenary versus parabola in log paper 28
Figure 3.6. Variation of n according to cable stress 28
Figure 3.7. Cable force subject to erection loads 29
Figure 3.8. Secont modulus of Elasticity 30
Figure 3.9. Tangent modulus of Elasticity 31
Figure 3.10. Bridge cable configurations used in Podolny's investigation 32
Figure 3.11. Plot of chord length required for linear behavior of the system having initial stresses of 0.5σDL and 0.8σDL(이미지참조) 33
Figure 3.12. Cable tension comparison. -Percent error 34
Figure 3.13. Cable tension compa-rison 34
Figure 3.14. P·△ effect in girder 35
Figure 3.15. Polt-% Error vs. Cable chord length for initial cable stress of 0.5σDL(이미지참조) 36
Figure 3.16. Polt-% Error vs. Cable chord length for initial cable stress of 0.8σDL(이미지참조) 36
Figure 3.17. Stress-Strain Curve Tangent Modulus 38
Figure 3.18. Stress-Strain Curve Secant Modulus 38
Figure 4.1. The matrix equation 40
Figure 4.2. The Components of the CG- matrix(이미지참조) 41
Figure 4.3. Load combination applied to structure for CG-(이미지참조) 41
Figure 4.4. Unit load applied to structure for K=(이미지참조) 42
Figure 4.5. Unbalanced cable forces in tower head 43
Figure 4.6. Schematic of systems represented by a matrix equation 44
Figure 4.7. Structural system corresponding to Table 3.1 44
Figure 5.1. Erection of Mainspan(FORWARD) 48
Figure 5.2. Disassembly of Mainspan(BACKWARDS) 49
Figure 5.3. Erection of Sidespan(FORWARD) 51
Figure 5.4. Disassembly of Sidespan.(BACKWARDS) 52
Figure 5.5. Computer File for Backwards Method 54
Figure 5.6. New Crane is introduced into construction 54
Figure 5.7. Introduction of new loading case into computer files 55
Figure 5.8. Flow chart of Computer Files with Nonlinearity introduced 56
Figure 7.1. Geometrical configuration 60
Figure 7.2. Cross section of stiffening girder 61
Figure 7.3. Computer model for erection procedure 62
Figure 7.4. Dead load moment distribution in the girder 62
Figure 7.5. Erection sequence by the Forward Method 63
Figure 7.6. Erection sequence by the Forward Method(continued) 64
Figure 7.7. The [Yn] matrix solved(이미지참조) 66
Figure 7.8. Graphical representation of the matrix equation of Fig.6.6 67
Figure 7.9. Flow chart of computer files with nonlinearity introduced 68
Figure 7.10. Disassembly sequence by the Backwards Method 69
Figure 7.11. Disassembly sequence by the Backwards Method(continued) 70
Figure 7.12. Initial forces determined 71
Figure 7.13. Equivalent modulus of elasticity of cables 73
Figure 7.14. Cable forces during erection procedure 74
Figure 7.15. Bending moment of girder during erection procedure 75