Scholarlink

<p>This study presents a three-dimensional discrete-element Freeze–Thaw Grain-Based Model (FT-GBM3D) to address key limitations of existing granite freeze–thaw simulations, including simplified 3D grain structures, oversimplified water distribution, and insufficient characterization of nonlinear damage. FT-GBM3D explicitly represents polymineralic 3D grains and introduces grain-boundary ice particles whose freezing–thawing deformation is driven by a transient temperature field obtained from the heat-conduction equation; the resulting nonuniform phase-change expansion pressure serves as the direct micro-damage driver. An exponential degradation law is further incorporated to capture the nonlinear deterioration of material properties, and the model is calibrated and validated against laboratory data. Numerical simulations show that FT-GBM3D captures the progressive reductions in granite strength and stiffness with increasing F-T cycles. The failure pattern shifts from inter-grain tensile cracking to predominantly intra-grain tensile failure, and crack morphology evolves from isolated features to a connected, propagating network. Force-chain analysis indicates that ice-particle expansion disrupts local load-transfer paths and induces stress concentrations, thereby accelerating structural weakening. Under uniaxial compression, F-T pre-damage lowers the crack-initiation stress and elastic energy-storage capacity, leading to concurrent decreases in peak strength and peak strain. The acoustic emission (AE) <i>b</i>-value first increases and then decreases with F-T cycling, implying a transition from diffuse microcracking to localized macrocracking. Overall, FT-GBM3D provides a 3D numerical framework for elucidating meso-scale F-T damage mechanisms and evaluating granite durability in cold-region rock engineering.</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

Numerical Investigation of Meso-Scale Damage Mechanisms and Mechanical Degradation in Granite Under Freeze–Thaw Cycling Using a 3D Grain-Based Model

  • 期刊论文

  • 发表日期：

    2026年7月10日

查看全文
  • Jinpeng Cao,
  • Shengyuan Song,
  • Jun Hu,
  • Xinrong Wang

摘要

This study presents a three-dimensional discrete-element Freeze–Thaw Grain-Based Model (FT-GBM3D) to address key limitations of existing granite freeze–thaw simulations, including simplified 3D grain structures, oversimplified water distribution, and insufficient characterization of nonlinear damage. FT-GBM3D explicitly represents polymineralic 3D grains and introduces grain-boundary ice particles whose freezing–thawing deformation is driven by a transient temperature field obtained from the heat-conduction equation; the resulting nonuniform phase-change expansion pressure serves as the direct micro-damage driver. An exponential degradation law is further incorporated to capture the nonlinear deterioration of material properties, and the model is calibrated and validated against laboratory data. Numerical simulations show that FT-GBM3D captures the progressive reductions in granite strength and stiffness with increasing F-T cycles. The failure pattern shifts from inter-grain tensile cracking to predominantly intra-grain tensile failure, and crack morphology evolves from isolated features to a connected, propagating network. Force-chain analysis indicates that ice-particle expansion disrupts local load-transfer paths and induces stress concentrations, thereby accelerating structural weakening. Under uniaxial compression, F-T pre-damage lowers the crack-initiation stress and elastic energy-storage capacity, leading to concurrent decreases in peak strength and peak strain. The acoustic emission (AE) b-value first increases and then decreases with F-T cycling, implying a transition from diffuse microcracking to localized macrocracking. Overall, FT-GBM3D provides a 3D numerical framework for elucidating meso-scale F-T damage mechanisms and evaluating granite durability in cold-region rock engineering.