부산항 연약지반 장기침하 원인 분석 및 지반개량 고도화 방안 연구

다국어 초록 (Multilingual Abstract)

Busan Port has undertaken port development in offshore areas extending from Gangseo-gu, Busan to Jinhae-gu, Changwon-si, Gyeongnam from 2006 to 2025 (with Phases 2–6 of the Busan New Port West Container Terminal currently under construction), and recently ushered in the era of fully automated ports, marked by the opening of New Port Pier 7. The Busan Port Jinhae New Port to be developed in the future, compared with the existing conventional terminals (Busan New Port), requires advanced soft-ground improvement during the port development process; therefore, this paper examines the direction for such advancement. Many of the terminal development projects at Busan Port are carried out under adverse conditions, as the area’s geographic characteristics often involve deep, ultra-soft ground. Based on lessons learned from conventional terminals and the recently opened Busan New Port Pier 7, this study analyzed various causes affecting long-term settlement prediction in soft ground. From a long-term perspective, Busan Port may experience major long-term load changes due to factors such as continued leasing and sales of logistics complexes, increases in cargo throughput, and expansion of facilities. In addition, load changes resulting from groundwater-level drawdown cannot be neglected. Under service loads, the target settlement varies with the groundwater level, and there can be significant differences in settlement depending on whether groundwater levels applied during construction and after completion differ. Given the characteristics of Busan Port, where land is created by reclaiming dredged material over soft clay ground, this study reviewed three advanced improvement measures using existing literature and design data. First, it examined settlement prediction by each stage of port construction. By reviewing various potential factors that may induce settlement throughout the site investigation, design, construction, monitoring, and operation phases, measures to minimize such settlement were proposed. Second, an investigation and analysis of vertical drain methods applied to Busan New Port and Jinhae New Port showed that the PBD method has been used in most cases, while soft-ground improvement using the DCM method has also been adopted in recent projects. Considering the deformation characteristics of the deep soft ground at Jinhae New Port, this study proposed applying the RVD method and a water surcharge (water preloading) method in place of the PBD method. Third, to enhance the quality of investigation results, it proposed establishing a standardized ground investigation manual that sufficiently reflects the marine environment and the characteristics of soft ground. Key Words : Soft ground improvement, Ground water level, Consolidation settlement, Advancement, Recycled-aggregate vertical drain method (RVD), Water surcharge (water preloading) method

목차 (Table of Contents)

• List of Tables·ⅲ
• List of Figuresⅳ
• ABSTRACT·ⅵ
• 1. 서론 1
• 1.1 연구 배경 1
• 1.2 연구 목적 3
• 1.3 연구 내용 5
• 2. 부산항 신항 및 진해신항 지반조건 6
• 2.1 국내 연약 점성토 지반 특성 6
• 2.1.1 개요 6
• 2.1.2 지역별 지반 특성 8
• 2.2 부산항 지반 특성 10
• 2.2.1 연약층 두께 및 침하량 10
• 2.2.2 물리적 특성 14
• 2.2.3 역학적 특성 18
• 3. 장기침하 원인 분석 22
• 3.1 장기적인 하중 변화 23
• 3.2 점토지반 장기적 침하 거동 28
• 4. 연약지반 침하 예측 고도화 및 중장기 추진 방안 35
• 4.1 항만개발 단계별 침하 예측 35
• 4.1.1 설계기준 및 지반조사 단계 35
• 4.1.2 설계 단계 38
• 4.1.3 시공 및 계측 단계 41
• 4.1.4 운영 단계 44
• 4.2 중장기 추진 방안 45
• 4.2.1 기존 연약지반개량 공법 장단점 검토 45
• 4.2.2 RVD(Recycled aggregate Vertical Drain) 공법 적용 48
• 4.2.3 하중재하공법 개발 51
• 4.2.4 항만 지반조사 분석 표준매뉴얼 개발 53
• 5. 결 론· 55
• 참고문헌· 57
• 초 록· 59