Scholarlink

<p>As coal mining extends to greater depths, evaluating the deformation and failure of surrounding tunnel rock under coupled seepage–stress conditions remain a significant challenge. In this study, triaxial compression tests were conducted on sandstone specimens under bilateral seepage conditions and combined with multi-scale experimental analyses. Increasing bottom seepage pressure reduced the peak stress and elasticity modulus by up to 28.5% and 20.0%, respectively, while increasing Poisson’s ratio by up to 44.1%. The peak permeability first decreases and then increases, with reduction rates ranging from 20.9% to 70.2%. Higher seepage pressure transformed the fracture morphology from non-planar to planar and promoted crack initiation by weakening the cementing minerals at both ends of the specimen. The hydraulic gradient also altered the fracture pattern from top-to-bottom propagation to crack initiation at both ends followed by inward propagation. Water–rock interaction further softened and hydrolysed the cementing minerals, weakening intergranular bonding and promoting intergranular fracture as the dominant failure mode. Based on calculus principles, a nonlinear constitutive model considering the non-uniform distribution of pore pressure was established, enabling accurate prediction of the mechanical response of sandstone under bilateral seepage conditions without parameter fitting. By integrating macroscopic mechanical testing, mesoscopic deformation monitoring, and microscopic fracture observations, this study reveals the relationship between seepage-induced mechanical degradation, strain localization, crack propagation, and mineral scale damage evolution, providing a comprehensive understanding of sandstone progressive failure under water–rock interaction.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Mechanical response and failure mechanisms of sandstone under water–rock interaction: a multi-scale study and constitutive modeling

  • 期刊论文

  • 发表日期：

    2026年7月30日

查看全文
  • Yian Chen,
  • Guangming Zhao,
  • Xuelin Yang,
  • Wensong Xu,
  • Xiang Cheng,
  • Shoujian Peng,
  • Jiang Xu

摘要

As coal mining extends to greater depths, evaluating the deformation and failure of surrounding tunnel rock under coupled seepage–stress conditions remain a significant challenge. In this study, triaxial compression tests were conducted on sandstone specimens under bilateral seepage conditions and combined with multi-scale experimental analyses. Increasing bottom seepage pressure reduced the peak stress and elasticity modulus by up to 28.5% and 20.0%, respectively, while increasing Poisson’s ratio by up to 44.1%. The peak permeability first decreases and then increases, with reduction rates ranging from 20.9% to 70.2%. Higher seepage pressure transformed the fracture morphology from non-planar to planar and promoted crack initiation by weakening the cementing minerals at both ends of the specimen. The hydraulic gradient also altered the fracture pattern from top-to-bottom propagation to crack initiation at both ends followed by inward propagation. Water–rock interaction further softened and hydrolysed the cementing minerals, weakening intergranular bonding and promoting intergranular fracture as the dominant failure mode. Based on calculus principles, a nonlinear constitutive model considering the non-uniform distribution of pore pressure was established, enabling accurate prediction of the mechanical response of sandstone under bilateral seepage conditions without parameter fitting. By integrating macroscopic mechanical testing, mesoscopic deformation monitoring, and microscopic fracture observations, this study reveals the relationship between seepage-induced mechanical degradation, strain localization, crack propagation, and mineral scale damage evolution, providing a comprehensive understanding of sandstone progressive failure under water–rock interaction.