外加材料对乳化沥青再生水泥稳定碎石混合料性能的影响

Effect of Additive Materials on Pavement Performance of Asphalt Emulsion Recycled Cement Stabilized Aggregate Mixture

通过室内试验评价了水泥、消石灰和消石灰矿渣粉3种外加材料对乳化沥青再生水(泥)稳(定)碎石混合料(乳化沥青再生混合料)路用性能的影响,利用扫描电镜观察了水泥乳化沥青胶浆与水稳碎石再生集料界面的微观结构,分析了乳化沥青再生混合料的强度形成机理.结果表明:水泥对乳化沥青再生混合料劈裂强度、水稳性和疲劳寿命提高最大,消石灰矿渣粉次之,消石灰最小.乳化沥青再生混合料中除乳化沥青外,水泥或消石灰矿渣粉也具有明显的胶结材料的作用,但消石灰不具有胶结材料的作用.水泥和乳化沥青水化产生的水化产物,在提高水泥乳化沥青胶浆黏度的同时,能与再生集料上的旧水化产物直接黏结,增大乳化沥青再生混合料中水泥乳化沥青胶浆与再生集料界面的黏结强度.

The effect of three types of additive materials, including cement, hydrated lime and hydrated lime-slag powder on the pavement performance of asphalt emulsion recycled cement stabilized aggregate mixture（asphalt emulsion recycled mixture） was investigated. Microstructure of interface between the cement-asphalt emulsion mastic and recycled cement stabilized aggregate（recycled aggregate） was observed by scan electron microscopy in order to analyze strength mechanism of the asphalt ＇emulsion recycled mixture. The results show that the cement as additive materials improves the indirect tensile strength, moisture resistance and fatigue life of asphalt emulsion recycled mixture best, followed by hydrated lime-slag powder, hydrated lime is the last. Cement or hydrated lime-slag powder plays the role of binder material as asphalt emulsion, but hydrated lime does not play the same role. Hydrated products formed by cement and asphalt emulsion can improve the viscosity of cement-asphalt emulsion mastic and firmly adhere to old hydrated products on the surface of recycled aggregate, therefore improving the adhesive strength of interface between the mastic and recycled aggregate in the asphalt emulsion recycled mixture.