Channel-Type Technique of Earthwork for Top-down Excavation and Its Application

Abstract

Abstract: A channel-type technique of earthwork was presented to resolve the conflict between the earthworks and struts construction in top-down excavations. In the new construction method, a working channel is cut in the middle of the excavation area at first. The remained soil on both sides of channel is quickly excavated in segmentation and transported through the channel. The strut system is constructed at the same time. Comparing to traditional excavation technology, the new method can not only promote the working efficiency and shorten construction time, but also reduce the deformation of retaining structures and surrounding environment. It is successfully applied in Shanghai West Railway Station project of Metro line #15. The deformation of diaphragm is controlled within permitted value, and the efficiency of construction is improved about 40% comparing to traditional method. Key words：

Key words: channel-type technique, earthwork, topdown method, deep excavation, efficiency of construction

CLC Number:

TU 47

XU An- Jun. Channel-Type Technique of Earthwork for Top-down Excavation and Its Application[J]. Journal of Shanghai Jiaotong University, 2012, 46(10): 1558-1562.

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