中文摘要：

利用扫描电镜结合DSC量热试验，研究了硅藻土微观结构与沥青之间相互作用的机理。发现硅藻土可以均匀分布于沥青中，并与沥青形成稳定体系．硅藻土所具有的特殊微观结构。能吸收沥青的油分，有助于改善沥青的路用性能．硅藻土加入沥青，不仅起填料的作用。更主要的是改性作用．结果表明。硅藻土改性沥青能显著提高混合料的高温稳定性，对低温抗裂性也有所改善，为硅藻土改性沥青的应用提供了理论依据．

英文摘要：

In order to recycle waste foamed plastic materials, the waste materials were firstly melt, then cooled and crushed, and so the waste foamed plastics aggregate （called EPS aggregate） are obtained. Because the heat conductivity of EPS aggregate is very low and density is also small, the EPS aggregate is proposed to be used to construct anti-freezing base course of road in this study for decreasing the frost depth and freezing heave. The CBR test and freezing test of mixture was performed in the laboratory, and a test road was constructed on the site. Result shows that EPS aggregate can improve the bearing capacity （CBR） of the roadbed material, especially when the roadbed material is weak clay. Meanwhile the frost depth of roadbed and base course that contains the EPS aggregate is reduced to a large extent, A this result is also proved by the site test of pavement. So mixing EPS aggregate can reduce the frost depth of road, which can improve the stability of road in freezing area.