Modeling and Evaluation of Aggregate Based on Influence of Geometry Morphology
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摘要:
目前流行的数字集料建模技术效率和质量低,参数不可控且不能兼顾集料的形状、棱角、纹理等多个几何形态参数,导致难以有效在细观层面研究集料几何形态参数对颗粒复合材料综合性能的影响. 针对上述问题,首先,研究了单一集料几何形态特征评价,并给出一种评价集料表面微观纹理和集料系统的数学方法;其次,基于3D Max提出一种新颖的单一集料数字模型设计技术,创建了带有不规则形状、无序棱角和精细表面纹理的集料数字模型;最后,基于PFC 3D并采用“颗粒替换法”创建颗粒复合材料数字模型,进而分析了实物模型和数字模型空隙率差异,并给出解决空隙率差异的数学方法. 在此基础上,通过单轴压缩试验研究了集料几何学特性对颗粒复合材料峰值抗压强度的影响. 研究结果表明:1) 给出的集料纹理评价数学方法能量化集料微观结构,而集料系统评价数学模型拓展了集料几何形态学评价指标;2) 颗粒复合材料实物模型和数字模型空隙率存在较大差异;3) 集料的几何学特征能提高集料之间的咬合互锁效应,用不规则颗粒替换粒径 ≥ 2.36 mm的球形颗粒可使复合材料的峰值抗压强度提高20.7%.
Abstract:The popular digital aggregate modeling technology has low efficiency and quality, with the parameters uncontrollable and not involving the shape, edges, texture and other geometric morphological parameters of the aggregate. Thus it is difficult to effectively study the effects of geometric-morphology parameters on the comprehensive performance of particle composites at a micro level. In view of this shortcoming, firstly, the evaluation method of the geometric morphology characteristics of a single aggregate is explored and a mathematical method is presented to evaluate the micro-texture of the aggregate surface, as well as the aggregate system. Secondly, with 3D Max, a novel digital model design method for a single aggregate is proposed to create a digital model with irregular shapes, disordered edges and corners, and fine surface textures. Finally, the particle-replacement method is used to create a digital model of particle composites with PFC 3D. Then the porosity difference between the physical and the digital models is analyzed and the method to solve the porosity difference is provided. On this basis, the influence of aggregate geometry on the peak compressive strength of particle composites is studied through uniaxial compression experiments. The results show that, 1) the mathematical evaluation method of aggregate texture can quantify the microstructure of the aggregate, and the mathematical model of aggregate system evaluation expands the geometric morphology evaluation indexes of the aggregate; 2) there is a big difference in the porosity between the physical and digital models of particle composites; 3) the geometric characteristics of the aggregate can improve the occlusal interlocking effect between aggregates, and the replacement of spherical particles with particle size ≥ 2.36 mm by irregular particles can increase the peak compressive strength of the composite by 20.7%.
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Key words:
- aggregate /
- modeling /
- geometrical morphology /
- composite /
- porosity
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表 1 集料建模精度试验方案
Table 1. Accuracy test schemes of aggregate modeling
试验方案
编号Ns/段 Ts/次 优化量/% T1 3 3 0 T2 4 3 0 T3 5 3 0 T4 3 4 0 T5 3 4 70 T6 3 4 40 -
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