When a tunnel is excavated in the water-rich soft rock stratum, the strength of the soft rock is greatly reduced due to the seepage of groundwater. The condition may result in engineering accidents, such as large deformation, limit invasion, and even local collapse of the tunnel. Therefore, it is very important to research the stability of the surrounding rock in the water-rich soft rock tunnel. The water-rich disturbance factor considering the seepage influence of groundwater and blasting disturbance is proposed, and the generalized Hoek–Brown strength criterion is modified on the basis of the immersion softening test of soft rock. In accordance with the classical elastic–plastic mechanics theory, the stress, strain, and displacement calculation formulas of the tunnel surrounding rock are derived. The displacement of tunnel surrounding rock is analyzed using the derived formula and the modified Hoek–Brown strength criterion and then compared with the measured value. Results show that the displacement of surrounding rock, which is calculated by modified Hoek–Brown strength criterion considering water-rich disturbance factor and the displacement calculation formula, is close to the measured deformation of surrounding rock in water-rich soft rock tunnel, and the error is small. Therefore, the modified Hoek–Brown strength criterion can be applied to the water-rich soft rock tunnel, and the derived displacement calculation formula can accurately calculate the deformation of tunnel surrounding rock. It is of great significance to the study of surrounding rock stability of water-rich soft rock tunnel.

中文翻译：

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修正Hoek-Brown强度准则在富水软岩隧道中的应用

在富水软岩地层开挖隧道时，由于地下水渗漏，软岩强度大大降低。这种情况可能导致隧道发生大变形、极限侵入甚至局部坍塌等工程事故。因此，研究富水软岩隧道围岩的稳定性具有重要意义。提出了考虑地下水渗流和爆破扰动影响的富水扰动因素，并在软岩浸没软化试验的基础上修改了广义Hoek-Brown强度准则。根据经典弹塑性力学理论，推导出隧道围岩的应力、应变和位移计算公式。利用推导公式和修正的Hoek-Brown强度准则对隧道围岩位移进行分析，并与实测值进行比较。结果表明，采用修正Hoek-Brown强度准则考虑富水扰动因素和位移计算公式计算的围岩位移与富水软岩隧道围岩实测变形接近，误差很小。因此，修正Hoek-Brown强度准则可应用于富水软岩隧道，推导的位移计算公式可准确计算隧道围岩变形。对富水软岩隧道围岩稳定性研究具有重要意义。