In micromechanical simulations of asphalt mixtures, complex shapes of asphalt mortar and coarse aggregates require numerous elements in the finite element (FE) representation. This makes simulation time-consuming with a high risk of failure. To conduct simulations with acceptable accuracy and low computational cost, an approach is proposed to simplify the geometry of mixture microstructures with error assessment due to simplification. The methodology comprises four main steps, as follows: (1) coarse aggregates in a specimen are three-dimensionally reconstructed to conduct surface triangulation; (2) surface triangles are then clustered with a predefined fitting accuracy using the least square method; (3) coarse aggregates are simplified as polyhedrons based on triangle clusters, and the asphalt mortar is then reconstructed using Boolean operations; and (4) the simulation error caused by simplification is assessed based on FE interpolation theory to ensure the reliability of the simulation. Two samples were prepared and then reconstructed for the simulation of a cyclic indirect tensile test. The volume difference for more than 95% aggregates was less than 5% for the two specimens. The difference of stress and strain curves of original and simplified models of the two specimens ranged from 2% to 4%, which indicates that the simulation solutions of the simplified and original microstructures were very close. Furthermore, computational time was significantly reduced due to the simplification of the aggregates. This method facilitates the reliable and highly efficient simulation of asphalt mixtures using the FE method.

中文翻译：

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使用有限元方法对沥青混合料成分进行微观力学模拟的形态学简化

在沥青混合料的微观力学模拟中，沥青砂浆和粗骨料的复杂形状需要有限元 (FE) 表示中的大量元素。这使得仿真耗时且失败的风险很高。为了以可接受的精度和低计算成本进行模拟，提出了一种方法来简化混合物微观结构的几何形状，并通过简化误差评估。该方法包括以下四个主要步骤：（1）对试件中的粗骨料进行三维重建，进行表面三角测量；(2) 然后使用最小二乘法以预定的拟合精度对表面三角形进行聚类；(3)基于三角形簇将粗集料简化为多面体，然后使用布尔运算重构沥青砂浆；(4)基于有限元插值理论对简化引起的仿真误差进行评估，以保证仿真的可靠性。制备了两个样品，然后重建以模拟循环间接拉伸试验。两个试样的超过 95% 的聚集体的体积差异小于 5%。两个试件的原始模型和简化模型的应力应变曲线差异在2%~4%之间，这表明简化和原始微观结构的模拟解非常接近。此外，由于聚合的简化，计算时间显着减少。该方法有助于使用有限元方法对沥青混合料进行可靠且高效的模拟。