Angular cracks are one of the types of cracks in asphalt mixtures that can be created due to the location of coarse aggregates as well as the weakness of the soft asphalt matrix (SAM). In this study, pure mode I was modeled to simulate the fracture behavior of hot mix asphalt (HMA) mixture containing angular cracks using the extended finite element method (XFEM). To improve HMA performance, calcium lignosulfonates (CL) additive and polyester fiber (PE), which were both environmentally and economically justifiable, were used. Numerical and experimental results showed that the proposed samples in both pure mode I (angular crack) and pure mode II (vertical crack) were able to model the fracture behavior of HMA; therefore, it can be used as suitable samples to study the pure mode crack deformation of HMA at low and intermediate temperatures. Also, the presence of coarse aggregate in the ligament section of the samples turned out to be an important factor in increasing fracture energy, fracture toughness, and reducing brittleness.

中文翻译：

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改性热拌沥青中低温下纯I型和纯II型抗断裂性能

角裂缝是沥青混合料中的一种裂缝，由于粗集料的位置以及软沥青基质 (SAM) 的弱点而可能产生。在本研究中，对纯模式 I 进行建模，以使用扩展有限元方法 (XFEM) 模拟包含角裂纹的热拌沥青 (HMA) 混合物的断裂行为。为了提高 HMA 性能，使用了在环境和经济上均合理的木质素磺酸钙 (CL) 添加剂和聚酯纤维 (PE)。数值和实验结果表明，所提出的纯模式 I（角裂纹）和纯模式 II（垂直裂纹）的样品都能够模拟 HMA 的断裂行为；因此，它可以作为合适的样品来研究 HMA 在低温和中温下的纯模式裂纹变形。还，