표제지
국문요약
목차
1. 서론 17
1.1. 연구 배경 및 필요성 17
1.2. 연구동향 19
1.3. 연구내용 및 방법 21
2. 액상화 현상 및 평가방법 23
2.1. 액상화 현상 23
2.1.1. 포화된 사질토의 동적거동 특성 23
2.1.2. 액상화 현상의 정의 26
2.1.3. 액상화 현상의 종류 28
2.2. 평가방법 30
2.2.1. 액상화 상세평가법 31
2.2.2. 유효응력해석을 통한 액상화 평가방법 34
3. 실내진동삼축시험 45
3.1. 실내진동삼축시험 개요 45
3.2. 실내진동삼축시험 원리 46
3.3. 실내진동삼축시험 장치 49
3.4. 시험 재료 50
3.5. 시험 조건 52
3.5.1. 상대밀도 차이에 따른 시험 수행 52
3.5.2. 하중재하 조건 53
3.6. 시험방법 및 과정 55
3.7. 실내진동삼축시험 결과 58
3.8. 액상화 진동저항응력비(CRR) 곡선 68
4. 유효응력모델을 이용한 수치해석 수행 71
4.1. Modified - FINN 모델 71
4.2. 유효응력개념 수치해석법 비교 73
4.3. 역해석 수행 74
4.3.1. 수치해석 모델링 및 경계조건 74
4.3.2. 수치해석을 위한 입력변수 산정 76
4.4. 역해석 수행 결과 78
5. 수치해석 결과 검증 및 매개변수 산정 82
5.1. 수치해석 결과 검증 82
5.2. 매개변수 산정 및 검증 84
5.2.1. 상대밀도별 매개변수 산정 84
5.2.2. 매개변수 산정식 검증 86
6. 결론 87
참고문헌 89
ABSTRACT 93
Table 2.1. Liquefaction assessment method 30
Table 2.2. Number of equivalent loads by earthquake magnitude 32
Table 3.1. Test physical properties of speciemens 50
Table 3.2. Test condition 52
Table 3.3. Test shear stress ratio condition 53
Table 3.4. Cyclic stress ratio and number of cycle relations 68
Table 3.5. Equation of cyclic resistance ratio curve by relative density 70
Table 4.1. Parameter comparison 73
Table 4.2. Numerical analysis input parameters 77
Table 4.3. Comparison of laboratory results and numerical analysis results 78
Table 5.1. Estimated parameters by relative density 84
Fig. 2.1. Loose sandy soil and dense sandy soil behavioral properties 24
Fig. 2.2. Effective stress - void ratio test result 25
Fig. 2.3. Schematic diagram of particle arrangement change caused by liquefaction 26
Fig. 2.4. Flow liquefaction & cyclic mobility area in p'-q curve 28
Fig. 2.5. Three cases of cyclic mobility 29
Fig. 2.6. Detail liquefaction assessment method flowchart 31
Fig. 2.7. Equivalence shear stress 32
Fig. 2.8. Cyclic resistance ratio curve example 33
Fig. 2.9. Comparison of theoretical equations and experiments of one-dimensional unloading curves 37
Fig. 2.10. Drain condition simple cyclic shear test result 39
Fig. 2.11. Volumetric strain change curve of strain controlled cyclic shear test 40
Fig. 2.12. Procedure for proposing deflection coefficient 41
Fig. 2.13. Volume strain curve reconstructed from the figure. 2.9 42
Fig. 2.14. Procedure for proposing deflection coefficient 44
Fig. 3.1. Shear stress distribution through cyclic triaxial test 47
Fig. 3.2. Seismic load reproduced through cyclic triaxial test 48
Fig. 3.3. This laboratory test equipment 49
Fig. 3.4. Grain size distribution curves of various ground materials 51
Fig. 3.5. Load deviatoric Stress by reative density 54
Fig. 3.6. Cyclic triaxial test process 56
Fig. 3.7. Cyclic triaxial test 57
Fig. 3.8. N-pore water pressure (Dr=40%) 59
Fig. 3.9. N-pore water pressure (Dr=60%) 60
Fig. 3.10. N-pore water pressure (Dr=80%) 61
Fig. 3.11. N-axial strain (Dr=40%) 62
Fig. 3.12. N-axial strain (Dr=60%) 63
Fig. 3.13. N-axial strain (Dr=80%) 64
Fig. 3.14. Axial strain - deviatoric stress (Dr=40%) 65
Fig. 3.15. Axial strain - deviatoric stress (Dr=60%) 66
Fig. 3.16. Axial strain - deviatoric stress (Dr=80%) 67
Fig. 3.17. Cyclic stress ratio and number of cycle relations curve 69
Fig. 3.18. Cyclic resistance stress ratio curve 70
Fig. 4.1. Cyclic triaxial test modling & boundary condition 75
Fig. 4.2. Shear wave velocity by relative density according to restraint pressure of silica sand 77
Fig. 4.3. Dr=40% pore water pressure comparion result 79
Fig. 4.4. Dr=60% pore water pressure comparion result 80
Fig. 4.5. Dr=80% pore water pressure comparion result 81
Fig. 5.1. Cyclic resistance stress ratio curve for comparison 82
Fig. 5.2. Parameter curve 85
Fig. 5.3. Dr=50% pore water pressure comparion result 86