A Novel Calculation Method of Process Load for Extra-Large Section Tunnels

The calculation of load and surrounding rock pressure of extra-large-section tunnels serves as an important premise for the design and construction of tunnel projects with extra-large sections. Based on the large-span section of the Shenzhen Liantang Tunnel (China), which is the largest highway tunnel in the world to date, this paper discusses the challenges existing in the calculation method of state load and surrounding rock pressure for extra-large-section tunnels and puts forward a novel calculation method for process load, which is suitable for extra-large-section highway tunnels. In the current work, we derived the related application correlations and improved the specific application steps, methods, and project models of the proposed calculation method. Both the rationality and feasibility of the calculation method were verified from a practical perspective by comparing the on-site data of surrounding rock pressure at the Liantang Tunnel with the calculated load, which provides a fundamental basis for the process design of tunnels.