基于细微观试验的水泥乳化沥青混合料空隙特征

Research on Air Void Features of Cement Asphalt Emulsion Mixtures from Microcosmic-test

摘要:

水泥乳化沥青混合料中的水泥和乳化沥青会发生相互作用，因而其空隙结构相对普通热拌沥青混合料复杂。采用CT设备研究乳化沥青用量和水泥用量对混合料中细观空隙分布和空隙特征的影响，基于扫描电镜进一步研究混合料中微观尺度的空隙结构。结果表明，随着乳化沥青用量的增大，混合料内部空隙尺寸有所减小，试件水平断面上的空隙总面积和平均单个空隙面积减小；水泥掺量超过3%时，混合料的CT可视空隙率明显增大，且空隙中的大尺寸空隙比例增高；由于乳化沥青及水泥材料的相互作用，水泥乳化沥青混合料的内部空隙结构比传统热拌沥青混合料疏松。

Abstract:

Cement and emulsified asphalt within the cement asphalt emulsion mixture would experienced interactions，which created more complex air void microstructure compared with normal hot mix asphalt. The influence on air void distribution and air void features from emulsion and cement content were studied by computed tomography, air void structure of micro-scale were further researched by scanning electron microscope. The results of the study showed that the air void size, total air void area and average single air void area of cement asphalt emulsion mixture specimens section was decreased with the increase of emulsion content; CT visible air void of mixtures and the ratio of big air void was increased observably when the cement content was more than 3%. Internal air void structure of cement asphalt emulsion mixtures maybe looser than traditional hot mix asphalt for the interaction of cement and emulsion asphalt.