Construction of Slurry Shield Tunnel under Huangpu River in Shanghai

摘要

This paper presents a case history of slurry shield tunnel constructed under Huangpu River in thernurban area of Shanghai. This tunnel is a highway tunnel used to connect the western part and therneastern part (the Pudong New Development Area) of Shanghai. The length of the tunnel was 2270.5rnm, of which 1310.5 m was constructed using slurry shield machine (SSM). The inner and outerrndiameters of the tunnel were 9.9 m and 11 m, respectively. The outer diameter of the shield was 11.22rnm. The soil type of the tunnel passing through was very soft mucky clay. This was the deltaic depositrnof Yangtze River. The soft mucky clay had the water content greater than its liquid limit, lowrnhydraulic conductivity, low shear strength, and high sensitivity. The sensitivity ratio of soft muckyrnclay at the construction site was around 5. There were about 457 m at the west side and 353 m at eastrnside passing under road and buildings. There were about 25 buildings in the west side and 15 buildingsrnin the east side above the tunnel. There were also many pipelines such as gas pipe, water-supply andrnsewerage pipes, and CATV and telephone cables etc. One building?s bottom slab was only 0.68 mrnabove tunnel crest. In order to reduce the disturbance to the surrounding ground, slurry pressure ofrnchamber was carefully regulated to the geotechnical and environment conditions during construction.rnCareful operation was adopted, movement of surrounding ground was monitored, and was feeded backrnto the construction operation. Some construction countermeasures were proposed based on thernmonitoring results during construction.