Abstract: A very large deep excavation project is located at the east and south sides of Fengshun Street and north side of the People’s Bank of China. The planned building area is approximately 91,040 square meters and the deepest excavation is approximately 19.5 meters below the proposed ground floor. Due to the high groundwater level, the excavation support is necessary otherwise the side soils would be collapsed under the seepage force. Based on the excavation requirements and the superstructure types, different excavation support systems are used: Segment AB was designed using combined soil nailed wall supporting system; Segment BCD used soil nailed wall plus soldier pile with ground anchor system; and Segment DEA utilized soldier pile with ground anchor as the primary support measure. The construction procedures, quality assurance and insitu monitoring at each segment are also presented in the paper.

Key words: Deep Excavation Support, Construction Technique, Construction Monitoring, Settlement, Dewatering Project