沥青混凝土级配曲线的数值设计方法与对有效弹性模量影响的研究  

Research on the Numerical Design Method of Asphalt Concrete Gradation Curve and Its Influence on the Effective Elastic Modulus

作　　者：刘誉宏 罗威 叶永 Yuhong Liu;Wei Luo;Yong Ye(Department of Engineering Mechanics,College of Hydraulic&Environmental Engineering,China Three Gorges University,Yichang,443002)

机构地区：[1]三峡大学水利与环境学院工程力学系,宜昌443002

出　　处：《固体力学学报》2021年第6期736-745,共10页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(11802162,11972216);宜昌市自然科学基金项目(2022)资助。

摘　　要：沥青混凝土有效性能的预测和评估是其在道路工程与大坝防渗等应用中的关键问题.论文利用细观随机建模技术和有限元方法研究了级配曲线对沥青混凝土有效弹性模量的影响.首先,基于改进的蒙特卡洛法分别实现了服从工程筛分级配曲线或给定函数级配曲线的沥青混凝土细观随机模型的高效生成;然后,利用建立的模型分析了骨料的含量、弹性模量和试样尺寸对沥青混凝土的有效弹性模量的影响,并与实验结果进行对比,验证了所建模型的可靠性;从而,预测了在AC-13级配范围内级配曲线的凹凸程度,即粗细骨料的组成比例对沥青混凝土有效弹性模量的影响.结果表明,级配曲线的凹凸程度对其有效弹性模量影响存在较大差异,级配曲线的下凹(粗骨料占比增大)会导致有效弹性模量迅速增大,级配曲线的上凸(细骨料占比增大)也会引起有效弹性模量略有上升;另外提出的随机建模方法可实现对级配曲线,即对粗细骨料组成比例的定制设计.The prediction and assessment of the effective property of asphalt concrete is a crucial issue in its application in road engineering and dam seepage prevention.This paper uses the meso-random modeling technology and the finite element method to study the effect of gradation curve on the effective elastic modulus of asphalt concrete.Primarily,the improved Monte Carlo method is employed to generate aggregates for controlling the unevenness of the gradation curve,and therefore,the asphalt concrete meso-random model,which obeys the engineering sieve grading distribution curve or the given function of grading curve,is generated efficiently.Then,the proposed model combined with the finite element method is used to analyze the effects of aggregate content,elastic modulus of aggregate,and size of specimen on the effective elastic modulus of asphalt concrete.The finite element method is used in the direct computation of the stress-strain field of asphalt concrete.And the effective elastic modulus obtained from the subsequent homogenization is compared with the experimental data.Finally,the effect of the concave-convex degree of the gradation curve in the AC-13 gradation range(i.e.,the influence of the composition ratio between coarse and fine aggregates)on the effective elastic modulus of asphalt concrete is predicted.The calculation results show that the concavity and convexity of the gradation curve play an important role in the effective elastic modulus.The concavity of the gradation curve results in the rapid increase of the effective elastic modulus,and the convexity of the gradation curve incurs the small rise of the effective elastic modulus.Besides,the proposed random modeling method can realize the customized design of the gradation curve.

关 键 词：沥青混凝土 级配曲线设计 随机投放 有效弹性模量 均匀化 

分 类 号：U414[交通运输工程—道路与铁道工程] TV431.5[水利工程—水工结构工程]