面向真实细观界面力学行为仿真的沥青混合料多精度三维重构及数值建模

项目名称： 面向真实细观界面力学行为仿真的沥青混合料多精度三维重构及数值建模

项目编号： No.51508147

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 建筑环境与结构工程学科

项目作者： 金灿

作者单位： 合肥工业大学

项目金额： 20万元

中文摘要： 在沥青混合料的力学特性预测中，真实细观界面力学行为的准确仿真对预测结果有着十分重要的影响。本申请以混合料中的沥青胶浆、各集料颗粒和空隙为三类建模对象，运用数字图形图像技术，首先从混合料X-ray CT断面图像中准确提取后两类对象的几何形状及空间分布信息，依据各对象的仿真敏感度为其选择合适建模精度，重构为拥有完整边界信息的各集料颗粒和空隙三维几何模型，进而通过图形学操作获得沥青胶浆几何模型并将其与各集料颗粒几何模型集成为混合料三维细观几何模型；在此基础上，检测集料颗粒—集料颗粒间和集料颗粒—沥青胶浆间的接触关系和状态，依此准确设置界面单元，并根据力学试验结果为各相材料及界面单元的属性赋值，最终获得能准确反映真实细观界面力学行为的混合料数值模型。旨在获得与沥青混合料真实细观结构高度一致的混合料三维几何模型的前提下，有效仿真混合料内部细观界面的力学行为，籍此提升混合料力学特性预测的可靠性和效率。

中文关键词： 沥青混合料；细观界面；三维重构；多精度；敏感度分析

英文摘要： Accurate evaluation of interfacial micromechanical behavior in asphalt mixture microstructure significantly affects the reliability of numerical prediction of mechanical performance of asphalt mixture. Asphalt mastic, aggregates and air voids are treated as three kinds of geometric modeling objects. With image processing and computer graphics techniques, aggregates and air voids are 3D reconstructed under appropriate modeling accuracies after the retrieval of shape and spatial distribution information from X-ray Computed Tomography images of asphalt mixture. With geometric models of aggregates and air voids, geometric model of asphalt mastic can be obtained by graphic operations. Geometric models of asphalt mastic and aggregates are assembled into the geometric model of the mixture microstructure. Consequently, contact information among aggregates and asphalt mastic is detected from the mixture microstructure model. As a result, according to the contact information, numerical elements can be configured and assigned with mechanical properties from corresponding mechanical experiments. Thus, the accurate interfacial micromechanical behavior in asphalt mixture microstructure is obtained by numerical model of the mixture. The reliability and efficiency of numerical prediction of mixture mechanical performance will be significantly improved.

英文关键词： Asphalt mixture;Microscopic interface;Three-dimensional reconstruction;Multi-accuracy;Sensitivity evaluation