Yang Liu, Hou Suwei, Yu Haibo
Zhengzhou Railway Vocational and Technical College, Zhengzhou 451460, China.
Beijing University of Civil Engineering and Architecture, Beijing 102600, China.
Materials (Basel). 2025 Jul 22;18(15):3426. doi: 10.3390/ma18153426.
This study investigated the fracture behavior of asphalt mixtures under indirect tensile loading by comparing the performance of homogenized and micromechanical finite element (FEMs) models based on the cohesive zone model (CZM). Five asphalt mixture types were tested experimentally, and both models were calibrated and validated using load-displacement curves from indirect tensile tests (IDTs). The micromechanical model, incorporating random aggregate generation and three-phase material definition, exhibited significantly higher predictive accuracy (R = 0.86-0.98) than the homogenized model (R = 0.66-0.77). The validated micromechanical model was further applied to quantify the impact of construction-related deficiencies-namely, increased air voids, non-continuous gradation, and aggregate segregation. The simulation results showed that higher void content (from 4% to 10%) reduced peak load by up to 35% and increased localized stress concentrations by up to 40%. Discontinuous gradation and uneven aggregate distribution also led to premature crack initiation and more complex fracture paths. These findings demonstrated the value of micromechanical modeling for evaluating sensitivity to mix design and compaction quality, providing a foundation for performance-based asphalt mixture optimization and durability improvement.
本研究通过比较基于粘结带模型（CZM）的均匀化有限元模型和细观力学有限元模型的性能，研究了沥青混合料在间接拉伸荷载下的断裂行为。对五种沥青混合料类型进行了试验测试，并使用间接拉伸试验（IDT）的荷载-位移曲线对两种模型进行了校准和验证。包含随机集料生成和三相材料定义的细观力学模型，其预测精度（R = 0.86 - 0.98）显著高于均匀化模型（R = 0.66 - 0.77）。经验证的细观力学模型进一步用于量化与施工相关的缺陷的影响，即增加的空隙率、不连续级配和集料离析。模拟结果表明，较高的空隙率（从4%增至10%）使峰值荷载降低了35%，局部应力集中增加了40%。不连续级配和不均匀的集料分布也导致了过早的裂纹萌生和更复杂的断裂路径。这些发现证明了细观力学建模在评估对混合料设计和压实质量的敏感性方面的价值，为基于性能的沥青混合料优化和耐久性提升奠定了基础。
