Surrounding rock pressure calculation based on time functions and stress release rate determination of deep soft rock tunnel: taking Zhonghe Tunnel as an example

• DOI: 10.3389/feart.2023.1223419
• Publication Date: 2023-07-21T19:22:06Z
• Authors: Xiao Ding; Xianghui Deng; Xuan Zhang; Rui Wang
• Keywords: time function; deep tunnel; Science; stress release rate; Q; 0211 other engineering and technologies; surrounding rock pressure; 02 engineering and technology; soft rock

On the basis of Zhonghe Tunnel project An-Lan Expressway, objective this study was to determine appropriate method calculating steel arch load and stress release rate during numerical simulation. First all, based on monitoring results six similar tunnel sections where surrounding rock exerts pressure arch, using time functions, history curve could be fitted, two formulas for stable in deep tunnels were compared, calculation model suitable constructed. Then, a simulation performed Flac3D, simulated Mana method. By comparing characteristic curves initial support under different rates, impact pattern summarized, an excavation determined value calculation. It found that better depict change over empirical formula Weibull function. A prediction made method, numerically 0.5. This thus provides future internal force analysis parameter design systems.