为解决深部地下工程面临的高水压支护设计和施工方面的理论难题，提出基于预锚注初期支护的高水压圆洞力学模型。首先，将岩土力学“流固耦合”原理应用于预锚注支护下开挖卸载力学模型的解析，获得应力场、位移场、渗流场的解析求解表达式，并通过有限元数值解对解析解的正确性进行验证； 其次，图形化展示径筋支护参数对初期支护区围岩的应力场的影响规律； 最后，基于最大有效剪应力求解和Hoek-Brown 岩体破坏准则，诠释采用预锚注支护来确保洞体安全开挖的原理，揭示径筋参数、洞口直径对开挖卸载安全的影响规律。结果表明： 1）解析解与数值解的规律基本一致； 2）预锚注初期支护可从2方面提高开挖后围岩的安全性，一是通过增大围岩径向应力以降低洞边固体有效剪应力，二是通过提高岩体完整性使得围岩屈服面外扩增大； 3）径筋参数对承载安全的影响程度由大至小依次为径筋直径、径筋数量、径筋长度； 4）径筋锚注支护作用获得的安全系数随着洞径的增大而逐渐降低。

 To address theoretical challenges in designing and constructing highwater pressure support systems for deep underground projects, a mechanical model for circular tunnels in highwater pressure environments, mainly supported by preanchoring and pregrouting, is proposed. To achieve this, the "fluidrock coupling" principle of geomechanics is applied to analyze the mechanical model of excavation unloading under anchorgrouting support. Furthermore, analytical solutions for stress, displacement, and seepage fields, which are subsequently validated against finite element solutions, is derived. Next, the effect of radial reinforcement support parameters on the stress field in the primarilysupported surrounding rock area is visually illustrated. Moreover, the principles behind presupport through reinforcement grouting are elucidated employing the HoekBrown criterion for rock mass failure and calculations of the maximum effective shear stress circle. Additionally, the influence of radial reinforcement parameters and tunnel diameter on excavation safety is explained. The results are as follows. (1) The analytical solution aligns with the numerical solution, confirming its accuracy. (2) Preanchoring and pregrouting support enhances excavation safety by increasing radial stress in the surrounding rock, thereby reducing maximum effective shear stress. Additionally, it improves the integrity of the rock mass, increasing the yield surface of the surrounding rock. (3) The significance of radial reinforcement parameters for safety follows this order: rockbolt diameter > number of rockbolts > rockbolt length. (4) Thus, the safety coefficient achieved through radial reinforcement anchoring grouting support gradually decreases as the tunnel diameter increases.〖JP〗

〖WT５《TNR#B》〗Keywords〖WT５《TNR》〗〖KG-*4〗: deep waterbearing surrounding rock; mechanical model for circular tunnel; primary support of preanchoring and pregrouting; safety analysis of excavation