Research on Construction Methods of Large Cross Section Tunnels in Loess on Zhengzhou-Xi'an High Speed Railway

摘要

In order to construct safely and quickly large cross section tunnels in loess on Zhengzhou-Xi'an High Speed Railway, a systematic research has been made on the mechanical characteristics of various construction methods and key techniques which affect the safety of construction, such as large spring of arch, locking bolts at spring of arch, system bolts, advance support, advance rate, bench length, support closing distance and time etc. By site tests and numerical analyses, key techniques for safe and quick construction of large cross section tunnels in loess are proposed to ensure the safety and quality of the railway construction and promote the development of tunnel construction techniques in loess in China.