(소개 : 서울지하철 건설현황)...1 1. 서언...3 1.1 공사개요...3 1.2 한강소개...7 1.3 지질현황...7 2. 하저터널의 설계...11 2.1 터널 단면설계...11 2.2 종, 횡단계획...12 2.3 방수계획...16 2.4 배수설계...16 3. 터널의 시공...18 3.1 굴착전방 지반조사...18 3.2 지반보강...24 3.3 굴착 및 지보시공...24 3.4 한강 중앙 인공섬 설치...31 3.5 구조물 시공...35 3.6 시공단계별 지하수 유출 및 처리...35 3.7 연약지반대 통과공법 시공결과...41 3.8 붕락구간 보강 시공결과...52 4. 유지관리...60 4.1 터널주변 지하수 관리...60 4.2 중앙집수정의 관리...60 4.3 구조물 관리를 위한 영구계측...62 5. 결언...66