Scholarlink

<p>This study employed a split Hopkinson pressure bar system to conduct dynamic compression tests on recycled aggregate concrete (RAC) specimens featuring diverse replacement ratios of recycled coarse aggregate, and scanning electron microscopy was employed to characterize the micro-morphology of the resulting fragments. Based on quantitative characterization of the old mortar content, a new three-dimensional mesoscale model for RAC was developed using self-written Python code. Unlike previous models that assume complete encapsulation of aggregates by old mortar, the proposed model incorporates six distinct material phases and accounts for the random spatial distribution, coverage, and thickness of adhered old mortar. Experimental results revealed that RAC exhibits higher strain-rate sensitivity and larger fragment sizes than natural aggregate concrete (NAC). The simulation results indicated that failure is primarily caused by tensile damage. Although the overall damage extent in RAC is comparable to NAC’s, damage localization is significantly more pronounced within weak interfacial phases. The old mortar content predominantly modulates the elastic modulus and crack width development in RAC, while its coverage plays a crucial role in determining compressive strength and crack density evolution.</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

A New Experiment-Based Numerical Model for Simulating the Mesoscopic Damage of Recycled Aggregate Concrete Under Impact Loading

  • 期刊论文

  • 发表日期：

    2026年5月21日

查看全文
  • N. Liu,
  • Z. Zhu,
  • L. Zhang,
  • T. Li,
  • Z. Cheng,
  • H. Su

摘要

This study employed a split Hopkinson pressure bar system to conduct dynamic compression tests on recycled aggregate concrete (RAC) specimens featuring diverse replacement ratios of recycled coarse aggregate, and scanning electron microscopy was employed to characterize the micro-morphology of the resulting fragments. Based on quantitative characterization of the old mortar content, a new three-dimensional mesoscale model for RAC was developed using self-written Python code. Unlike previous models that assume complete encapsulation of aggregates by old mortar, the proposed model incorporates six distinct material phases and accounts for the random spatial distribution, coverage, and thickness of adhered old mortar. Experimental results revealed that RAC exhibits higher strain-rate sensitivity and larger fragment sizes than natural aggregate concrete (NAC). The simulation results indicated that failure is primarily caused by tensile damage. Although the overall damage extent in RAC is comparable to NAC’s, damage localization is significantly more pronounced within weak interfacial phases. The old mortar content predominantly modulates the elastic modulus and crack width development in RAC, while its coverage plays a crucial role in determining compressive strength and crack density evolution.