Research Of New Cold Mix And Cold Laid Emulsified Asphalt Mixture

Cold asphalt mixture can be handled at ambient air temperature and thus is regarded as energy saving, convenient for storage, transportation and construction, and can extend the construction season. However, it is commonly used in preventative maintenance of pavement as slurry seal and Micro-surfacing, not as structural layer due to its inferior performance to Hot Asphalt Mixture(HAM).This paper aims to develop a new cold mix and cold laid emulsified asphalt mixture to promote the application of cold mixture technology. By the means of using SBS polymer modified emulsified asphalt and cement to improve the performance of cold asphalt mixture.The cold asphalt mixture can meet the requirements of structural layer.Proportion design of AC-13 and AC-16 asphalt mixture using SBS polymer modified emulsified asphalt is carried out. Devise the emulsified asphalt test methods by the research of mixing sequence, compaction molding method and curing condition. Determine the mixture gradation composition and the best dosage of emulsion.This paper dose the performance evaluation and comparison of cold mix and cold laid emulsified asphalt mixture with different cement contents(0%、1%、2%、3%)and HAM which included mechanical properties, high temperature stability, water stability, low temperature crack resistance based on the Marshall test, split test, rutting test, immersion marshall test, freeze-thaw splitting test, bending-beam test at low temperature. Results show that, Cold asphalt mixture using polymer modified emulsion performed very well in rutting resistance performance. When the cement contents increase, the mechanical properties, high temperature stability and water stability of the emulsified asphalt mixture are increased, but the low temperature crack resistance is decreased. The performance of cold mix and cold laid emulsified asphalt mixture can achieve to and even be above the level of HAM when the cement content is controlled in 1%~1.5%.This paper summarizes the construction technology of cold mix and cold laid emulsified asphalt mixture. Emulsified asphalt mixture has significant economic and social profits compared with HAM.It is concluded that cold mix and cold laid emulsified asphalt mixture is a great kind of pavement materal, it can meet the level of highway surface layer building, and it deserves to be popularized and applied in our country’s road building.