Wang Zhenhua, Wang Zecheng, Chen Xin, Wang Gang, Li Dongwei
School of Civil and Architecture Engineering, East China University of Technology, Nanchang, 330013, China.
School of Civil Engineering, Shaoxing University, Shaoxing, 312000, China.
Sci Rep. 2025 Jan 6;15(1):891. doi: 10.1038/s41598-025-85333-3.
It is significant to study the stability of surrounding rock in soft rock tunnels to ensure construction safety and improve efficiency. Through triaxial shear tests on soft rock at various confining pressures, we observed the failure characteristics transitioning from strain softening to strain hardening as confining pressure increases. An improved Hoek-Brown strength criterion has been proposed to characterize the critical confining pressure effect of soft rock, with tensile strength in the tensile zone aligning with experimental results, showing an error of less than 5%. By assuming that the micro-unit strength of soft rock follows a two-parameter Weibull distribution, we constructed a statistical damage constitutive model for soft rock in mountain tunnels. This model provides a more realistic depiction of damage change, failure processes, and stress-strain evolution in soft rock, thereby validating its scientific and rational foundation. The research findings can serve as a valuable reference for mountain tunnel construction.
研究软岩隧道围岩稳定性对于确保施工安全和提高施工效率具有重要意义。通过对不同围压下的软岩进行三轴剪切试验，我们观察到随着围压增加，破坏特征从应变软化转变为应变硬化。提出了一种改进的Hoek-Brown强度准则来表征软岩的临界围压效应，拉应力区的抗拉强度与试验结果吻合，误差小于5%。通过假设软岩的微单元强度服从双参数威布尔分布，构建了山岭隧道软岩的统计损伤本构模型。该模型更真实地描述了软岩中的损伤变化、破坏过程和应力应变演化，从而验证了其科学合理性。研究结果可为山岭隧道施工提供有价值的参考。
