沥青混合料虚拟单轴蠕变试验方法  

Virtual Uniaxial Creep Testing Method for Asphalt Mixture

作　　者：陈明[1,2] 李霖[2] 赵新惠[2] 万成[3] 

机构地区：[1]长安大学,陕西西安710064 [2]交通运输部科学研究院,北京100029 [3]华南理工大学土木与交通学院,广东广州510640

出　　处：《公路交通科技》2015年第5期13-18,共6页Journal of Highway and Transportation Research and Development

基　　金：中央高校基本科研业务费专项资金(20112B0017);中国博士后科学基金(20110490092)

摘　　要：为了更为准确地预测混合料的变形,验证虚拟单轴蠕变试验方法的可行性,选用不同粗细级配的沥青混合料,利用X-ray CT扫描无损沥青混合料试件,获取其内部结构(集料、砂胶和空隙)精细分布信息;根据三维重构理论和开发的重构算法,构建基于真实细观尺度分布的沥青混合料三维虚拟试样;基于沥青砂胶的Burgers黏弹本构关系,根据Boltzmann线性叠加原理和Laplace数学理论,将沥青砂胶的黏弹特性转换为有限元软件可识别的Prony参数,进行虚拟单轴蠕变试验。结果表明预测的变形结果与实测变形结果非常吻合。虚拟单轴蠕变试验方法真实反映了不同混合料级配的不同变形特性,克服了传统基于均质体模型进行数值模拟的缺陷,实现了沥青混合料单轴蠕变试验的初步仿真。In order to predict the deformation of asphalt mixture more accurately and verify the feasibility of virtual uniaxial creep testing method, selecting different gradations, X-ray CT is used to scan the non- destructive asphalt specimens, and the finely distributed information of the microstructure of asphalt mixture including aggregate, sand mastic and air voids are captured. According to the 3D reconstruction theory and the developed algorithm, the 3D virtual specimen which reflects the real mieroscale distribution of asphalt mixture is built up. Considering the Burgers visco-elastic consecutive relation of sand mastic, in terms of Boltzmann linear superposition principle and Laplace theory, the visco-elastic character of sand mastic is transformed to the Prony parameters which can be identified by finite element. Finally, the virtual uniaxial creep testing is conducted. The result shows that the predicted deformations are agree well with the testing result. The virtual uniaxial creep testing method truly reflects different deformations of different gradations, by which the defects of conventional numerical simulation based on homogeneous specimen are overcome, and the initial simulation by uniaxial creep test of asphalt mixture is achieved.

关 键 词：道路工程 沥青混合料 单轴蠕变 虚拟试验 变形 

分 类 号：U414.1[交通运输工程—道路与铁道工程]