摘要
为研究沥青混合料的骨架特征与其剪切模量的关系,基于数字图像技术实现粗集料接触特性分析,提出以平均半径r作为混合料粗细集料分界点的动态划分方法,确定以最小计算粒径的23%作为接触阈值,结合散体力学理论与数字图像技术实现剪切模量预估模型的修正。结果表明:基于散体力学理论的均匀应变模型与静力学模型均能准确估算材料的剪切模量;剪切模量G′较抗剪强度τD更能反映沥青混合料的抗车辙性能;单元面积内接触点数量S1可作为衡量集料空间特性的指标;沥青性能决定了集料切向弹性刚度ks与量纲一的刚度比值λ,同种沥青的混合料λ值基本相同。
To study the relationship between the skeleton properties of asphalt mixture and shear modulus, bases on the digital image processing technology for the analysis of coarse aggregate contact characteristics, average radius r was proposed as the demarcation point of aggrate, and 23% of minimum calculated diameter was determined as the contact threshold. The granular mechanics and digital image processing technology were used to validate the shear modulus prediction model for asphalt mixtures. The results indicate that the uniform strain model and static model are both practical in predicting the shear modulus; the shear modulus G＇ is better in reflecting the anti-rutting performance of mixtures than shear strength rD; the number of aggregate contact points in unit cell S1 is adopted to evaluate the spatial characteristics; the aggregate tangential elastic stiffness ks and the value of dimensionless stiffness ratio it are determined by the performance of asphalt, and the values of it are the same when the same asphalt is added into the mixtures.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2013年第6期38-46,共9页
China Journal of Highway and Transport
基金
国家自然科学基金项目(50278037
51008131)
关键词
道路工程
沥青混合料
散体力学
剪切模量
数字图像技术
接触点
road engineering
asphalt mixture
granular mechanics
shear modulus
digital imageprocessing technology
contact point
