Scholarlink

<p>This study proposes a multi-scale framework integrating experimental characterization, microstructural analysis, and molecular dynamics (MD) simulations to evaluate the fatigue performance of asphalt mastic in which recycled concrete powder (RCP) replaces limestone powder (LP). Linear amplitude sweep tests reveal a systematic shift from stiffness to toughness dominated behavior with increasing RCP content: the initial shear modulus decreases from 91.89&#xa0;kPa to 28.92&#xa0;kPa, while the critical strain increases from 7.7% to 10.13%. The optimal 50–75% replacement range maintains moderate stiffness (68.79–72.86&#xa0;kPa) and achieves a critical strain of 8.19–8.58% with a fatigue life ratio exceeding 1.5. An energy-based damage evaluation system (Energy Damage Coefficient (EDC), Cumulative Energy Damage Index (CEDI), η) identifies a pronounced performance threshold at 50% replacement, beyond which damage accumulation is substantially suppressed. MD simulations show that higher RCP content progressively enhances interfacial binding energy (from − 17,638 to -76,411&#xa0;kcal/mol) and reduces the radius of gyration (from 1.03 to 0.87&#xa0;nm), establishing a “high free volume–compact molecular chain” configuration. Critical molecular thresholds (free volume fraction ≥ 17%, radius of gyration ≤ 0.98&#xa0;nm, interfacial binding energy ≥ 25,000&#xa0;kcal/mol) are identified as the mechanistic basis for optimal fatigue resistance. A modified viscoelastic continuum damage (VECD) model incorporating these molecular-scale parameters reduces prediction errors from &gt; 30% to within ± 15% across temperatures of 5–60&#xa0;°C, frequencies of 0.1–25&#xa0;Hz, and strain levels of 0.5-8%. At 75% RCP, embodied carbon is reduced by 0.85&#xa0;kg CO<sub>2</sub>-eq/t and material costs by 187.4 RMB/t, with full compatibility with conventional production processes. This research provides a mechanistic understanding, a validated predictive model, and a practical pathway for the high-value recycling of construction solid waste in sustainable pavement engineering.</p> Graphical Abstract <p></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

Fatigue Performance and Service Life Prediction of Asphalt Mastic Containing Recycled Concrete Powder

  • 期刊论文

  • 发表日期：

    2026年5月7日

查看全文
  • Huixia Li,
  • Yunjie Xia,
  • Yan Liang,
  • Taozhi Xu,
  • Xiangbing Xie,
  • Jinggan Shao

摘要

This study proposes a multi-scale framework integrating experimental characterization, microstructural analysis, and molecular dynamics (MD) simulations to evaluate the fatigue performance of asphalt mastic in which recycled concrete powder (RCP) replaces limestone powder (LP). Linear amplitude sweep tests reveal a systematic shift from stiffness to toughness dominated behavior with increasing RCP content: the initial shear modulus decreases from 91.89 kPa to 28.92 kPa, while the critical strain increases from 7.7% to 10.13%. The optimal 50–75% replacement range maintains moderate stiffness (68.79–72.86 kPa) and achieves a critical strain of 8.19–8.58% with a fatigue life ratio exceeding 1.5. An energy-based damage evaluation system (Energy Damage Coefficient (EDC), Cumulative Energy Damage Index (CEDI), η) identifies a pronounced performance threshold at 50% replacement, beyond which damage accumulation is substantially suppressed. MD simulations show that higher RCP content progressively enhances interfacial binding energy (from − 17,638 to -76,411 kcal/mol) and reduces the radius of gyration (from 1.03 to 0.87 nm), establishing a “high free volume–compact molecular chain” configuration. Critical molecular thresholds (free volume fraction ≥ 17%, radius of gyration ≤ 0.98 nm, interfacial binding energy ≥ 25,000 kcal/mol) are identified as the mechanistic basis for optimal fatigue resistance. A modified viscoelastic continuum damage (VECD) model incorporating these molecular-scale parameters reduces prediction errors from > 30% to within ± 15% across temperatures of 5–60 °C, frequencies of 0.1–25 Hz, and strain levels of 0.5-8%. At 75% RCP, embodied carbon is reduced by 0.85 kg CO2-eq/t and material costs by 187.4 RMB/t, with full compatibility with conventional production processes. This research provides a mechanistic understanding, a validated predictive model, and a practical pathway for the high-value recycling of construction solid waste in sustainable pavement engineering.

Graphical Abstract