The Study For Construction Method Of Diaphragm Wall In Hangzhou

Underground continuous wall technology originated in Europe. In 1920 underground continuous wall patent was first proposed by Germany. During the decade from 1950 to 1960 underground continuous wall technology made a surprising development with the economic development after the World War II, including trench machinery, construction technology and the application of bentonite slurry in foundation engineering. After the 1980s, many countries make great efforts to improve and research trench machinery and ancillary equipment, and improve joint form, in order to improve the efficiency of construction of underground continuous wall, toward a deeper and more complex goals.With the construction of Hangzhou Metro Line 1, deep foundation pit supporting technology will be developed rapidly in the Hangzhou area, especially the underground continuous wall construction technology.The application of underground continuous wall in the deep pit can be traced back to the 1990s deep foundation pit engineering of Jiebai Building, and later the Hyatt Hotel in Hangzhou, Zhejiang securities building, Hangzhou municipal commercial bank building, Hangzhou Guangdong development bank building, as well as the recent Hangzhou subway station, Hangzhou dragon hotel. Underground continuous wall as a mature deep foundation pit supporting programme has been widely used. Even more early underground continuous wall had been applied in Hangzhou, but due to various reasons, the technology was not spread, of which the most important reason is that the geological situation of Hangzhou is poor, there are large amounts of silt soil in the soil layer and the water table is relatively high.The difficulty and risks of underground continuous wall in the silt layer is much higher than in the sand. In the current construction of the underground wall station, the performance is not very good, due to various construction units from different regions, the lack understanding of Hangzhou Geological condition and can't realize that it's not harmful. during the construction many problems has been exposed, the most serious problem is the ratio of the mud and its recycling, screening of the joint form, and how to prevent flow around , how to solve it, as well as the selection of a slot technics and machine.In the finality,the problems requiring further studies are discussed.