First application of mechanized method using earth pressure balance TBM with large horseshoe-shaped cross section to loess mountain tunnel: A case study of Baicheng tunnel. (August 2022)

• Record Type: Journal Article
• Authors: Qiu, Wenge; Ai, Xufeng; Zheng, Yuchao
• Is Part Of: Tunnelling and underground space technology. Volume 126(2022)
• Publication Date: 2022-08
• Subjects: Loess mountain tunnel -- Horseshoe-shaped TBM -- Noncircular TBM -- Construction technique -- Construction method; Tunneling -- Periodicals; Underground construction -- Periodicals; Tunnels -- Periodicals; Underground areas -- Periodicals; 624.193
• DOI: 10.1016/j.tust.2022.104547
• Languages: English
• ISSNs: 0886-7798

Abstract

Highlights: The mechanized method using a horseshoe-shaped tunnel boring machine was developed. The mechanized method was first applied to a loess mountain tunnel. The key construction techniques suitable for loess mountain tunnels were developed. Blind excavation spots caused difficulties in the advancing and mucking. Abstract: The Baicheng Tunnel is a railway mountain tunnel with a large cross section located in a loess area. In view of the limitations of the available construction technology, a proposal was made to construct the tunnel using a tunnel boring machine (TBM) with a horseshoe-shaped cross section, with the aim of achieving a better balance of safety, quality, environmental impact, progress, and investment. Finally, a novel tunneling method was adopted after demonstrating its feasibility. The world's first large-cross section horseshoe-shaped earth pressure balance TBM was developed for the Baicheng Tunnel project, and a horseshoe-shaped segmental tunnel lining was applied. This was the first application of the mechanized method using a TBM to a loess mountain tunnel. Through exploration and practice, key construction techniques were developed, and unexpected difficulties in advancing and mucking were encountered. The Baicheng Tunnel was successfully completed; however, there are still many technical problems to be studied for realizing the potential of the mechanized method. This study provides valuable information for the design and construction of noncircular TBM tunnels and loess mountain tunnels, along with relevant research.