Application of AGF to Shanghai Metro 1 Une construction

Since introduction of artificially ground freezing(AGF) into China in 1956, more than 400 shafts have been sunk by using it with 66.7km long in total for coal mining. However, examples in other fields are few in China. This paper introduces recent application of AGF to construction of bypass channels in Shanghai Metro 1 # line to tackle failure of some traditional techniques in reinforcing silt soil. The following problems were solved by using AGF: a) silt rushing out from work face of the bypass channel at Sinan Road; b) large ground settlement caused by large amount of silt rushing in excavating; and c) reinforcing silt soil around the bypass channel at Changsha Road from the tunnel because of failure of jet grouting. It was the success of AGF application that ensured the trail run on 10th April 1995.