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.

References

［1］贾坚. 逆作开挖深基坑控制卸载变形的方法与实践［J］. 岩土工程学报, 2007, 29(2):304308.
JIA Jian. Deflection controlling measures and practices of deep foundation pits by use of topdown excavation method［J］. Chinese Journal of Geotechnical Engineering, 2007, 29(2): 304308.
［2］钟卫斌. 深基坑“半逆作法”施工实践［J］. 岩土力学, 2004, 25(3): 495500.
ZHONG Weibin. Construction practice of “semiinverse method” for deep foundation pit［J］. Rock and Soil Mechanics, 2004, 25(3): 495500.
［3］王卫东, 王建华. 深基坑支护结构与主体结构相结合的设计、分析与实例［M］. 北京:中国建筑工业出版社，2007.
［4］庄剑峰, 谢小松. “半逆作法”在大型深基坑开挖中的应用［J］. 建筑技术, 2007, 38(12): 893895.
ZHUANG Jianfeng, XIE Xiaosong. Semireverse construction method applied to the excavation of a large deep foundation pit［J］. Architecture Technology, 2007, 38(12): 893895.
［5］周臻全. 中心顺作—周边踏步式逆作施工工艺及关键技术［J］. 岩土工程学报, 2010, 32(S2): 455458.
ZHOU Zhenquan. Central part by bottomup method and peripheral part by steplike topdown method construction craft and key technologies［J］. Chinese Journal of Geotechnical Engineering, 2010, 32(S2): 455458.
［6］包旭范, 庄丽, 吕培林, 等. 大型软土基坑中心岛法施工中土台预留宽度的研究［J］. 岩土工程学报, 2006, 28(10): 12081212.
BAO Xufan, ZHUANG Li, L Peilin, et al. Study on mound width remained during the construction of central island for large foundation pits in soft soils［J］. Chinese Journal of Geotechnical Engineering, 2006, 28(10): 12081212.
［7］梁志荣, 李忠诚, 赵军, 等. 基于极限抗力的基坑中心岛施工留土宽度分析［J］. 岩土工程学报, 2010, 32(S2): 335338.
LIANG Zhirong, LI Zhongcheng, ZHAO Jun, et al. Retained soil width in midisland excavation method based on ultimate resistance method［J］. Chinese Journal of Geotechnical Engineering, 2010, 32(S2): 335338.
［8］王建华, 徐中华, 王卫东, 等. 支护结构与主体地下结构相结合的深基坑变形特性分析［J］. 岩土工程学报, 2007, 29 (12):19891903.
WANG Jianhua,XU Zhonghua,WANG Weidong, et al.Analysis of deformation behavior of deep excavations supported by permanent structure［J］. Chinese Journal of Geotechnical Engineering, 2007, 29 (12):19891903.
［9］丁勇春, 王建华, 徐中华, 等. 上海软土地区地铁车站深基坑的变形特性［J］. 上海交通大学学报, 2008, 42(11): 18711875.
DING Yongchun,WANG Jianhua,XU Zhonghua, et al.Deformation characteristics of deep excavations for metro stations in Shanghai soft soil deposits［J］. Journal of Shanghai Jiaotong University, 2008, 42 (11): 18711875.

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