Tunnel and Underground SpaceISSN:1225-1275(Print) 2287-1748(Online)한국암반공학회

Recently, with the development of 400km/h high-speed trains and their application in design, there has been an increase in high-speed railway large-section tunnel design cases aimed at addressing issues such as low pressure inside tunnels and passenger discomfort due to pressure changes. As the design speed of 400km/h is applied, the length of high-speed railway large-section tunnels is expected to increase. However, current design standards do not present a standard support pattern for high-speed railway large-section tunnels. This study proposes a standard support pattern suitable for 400 km/h-class high-speed railway large-section tunnels to ensure excavation stability and improve ground response. After analyzing existing standard support pattern cases for large-section tunnels and design standards, the suitability of the proposed support pattern was verified through numerical analysis. Furthermore, by reviewing the stress safety factor of the support, the support amount was optimized, and the bottom excavation face was increased by verifying the appropriate support length, leading to the proposal of an improved standard support pattern for 400 km/h-class large-section tunnels.