Experimental Research On Vibratory Mixing Asphalt Cement Mortar

Emulsified asphalt cement mortar is made of cement, emulsified asphalt, sand, water, additives and other raw materials, after the hydration cement and asphalt emulsion breaking interaction and then forming a composite material. It is the key structural materials of the high-speed railway ballastless track.This paper discusses the major indicators which has effect on emulsified asphalt cement mortar performance, and shows the testing methods of the site about mortar temperature, extension, fluidity, separation, gas content, unit volume quality, expansion rate, elastic modulus, flexural strength, compressive strength, fatigue resistance and other indicators.It analyzes the formation mechanism of cement mortar emulsified asphalt, including the cement hydration mechanism, the mechanism of emulsified asphalt emulsion breaking, CA mortar mixing process involving the physical and chemical processes of asphalt emulsion breaking and cement hydration, the mechanism of defoamer, etc, and provides a theoretical basis for experimental research.The results show that the vibration mixer mixing parameters of each group when the indicators of the emulsified asphalt cement mortar essential meet the requirements; Recommended mixing device parameters are:vibration frequency for 200rad/s～250 rad/s, amplitude to 1.5mm, emulsified asphalt and water mixing speed for 20r/min, emulsified asphalt and water mixing time for 1.5min, high-speed stirring speed for 40r/min～60 r/min, high-speed stirring time for 2.0min～3.0min, defoaming speed for 40 r/min～30r/min, defoaming time for 2.0min; recommended reasonable feed sequence is:emulsified asphalt+ water+water reducing agent→powder→defoaming agent→product.The analysis of the microstructure about emulsified asphalt cement mortar are mainly carried out via three aspects which are the distribution of stomata, the distribution of stomata, slurry structure, and the aggregate distribution. The results show that when mixing technology and parameters changing, it will really have an important impact on CA mortar. When the mixing technology and parameters are selected appropriate, the microstructure of CA mortar could be improved, finally the CA mortar performance could be ensured. In this thesis, it studies the interaction mechanism of vibration mixing device and emulsified asphalt cement mortar material, mainly through testing to determine the changing regularity of various indicators of the formation of mortar material when the mixing device vibration parameters and process parameters changing. The conclusions from the research provide foundations to improve emulsified asphalt cement mortar performance and its productivity for the industrial production.