排水沥青混合料各向异性空隙结构对渗水特性的影响  

Study on the Influence of Anisotropy Air Voids Structure in Porous Asphalt Mixture on Seepage Characteristics

作　　者：肖鑫[1] 张肖宁[1] XIAO Xin ;ZHANG Xiaoning(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,Guangdong,China)

机构地区：[1]华南理工大学土木与交通学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2018年第1期91-96,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51038004);国家重大科技支撑计划项目(2011BAG07B03)~~

摘　　要：为研究排水沥青混合料各向异性空隙结构对渗水特性的影响,以拓展的达西定律为理论基础,基于工业CT获取排水沥青混合料的空隙细观分布特征,建立了排水沥青混合料的渗水数值模型,并采用有限体积法分析了水在排水沥青混合料结构内部的流动特征;截取长方体试件作为特征体元来描述排水沥青混合料的各向异性渗透性能.研究表明:排水沥青混合料中空隙分布不均匀,横向的连通空隙率大于竖向,且单个空隙面积也比竖向大,空隙率的各向异性分布使得混合料试件渗透性也表现出各向异性;横向两个方向的渗透系数相近,且约为竖向的2倍;在进行渗透性分析时,在横向可把排水沥青混合料看成是各向同性体,而横向与竖向同时分析时应考虑为各向异性体.In order to study the influence of anisotropy air voids structure in porous asphalt mixture on seepage characteristics,the theory of Darcy Law was adopted.Air voids micro-distribution characteristics of porous asphalt mixture are obtained on the basis of industrial CT,seepage flow numerical model of porous asphalt mixture is established and the internal flow characteristics of water within porous asphalt mixture are analyzed by the finite volume method.In the meantime,a cuboid test-piece is designed as a representative volume element to describe the anisotropy permeability performance of the porous asphalt mixture.The results demonstrate that the porous asphalt mixture features an uneven distribution in light of air voids,denser connecting air voids and larger area per single air void in horizontal direction than that in vertical direction.The results also indicate that because of the anisotropy of air voids,the permeability performance of the mixture sample also features anisotropy,the permeability coefficients in two horizontal directions tend to be very close,which are about two times those of the vertical directions.Thus in terms of the analysis of the permeability performance,the porous asphalt mixture can be considered as isotropy horizontally or as anisotropy when analyzed both horizontally and vertically.

关 键 词：道路工程 排水沥青混合料 各向异性体 空隙结构 渗透性 渗透系数 

分 类 号：U416.217[交通运输工程—道路与铁道工程]