Rearch On Dry Pressing Voidge Of The Mineral Powder In Laboratory

Asphalt mixture is composed of asphalt and aggregate, asphalt mortar consists of asphalt and mineral powder. Although asphalt mortar is a small proportion of asphalt mixture, it plays a very important role in the pavement performance of asphalt mixture. It always focuses on the selection and the improvement of asphalt in engineering practice in China and abroad, ore selection and study of filler are in inadequate attention.Facing with the above problems, researching on the properties of mineral filler bases on the basic in China and abroad, and studying mainly on the dry pressing voidage of mineral filler with combining the method of theory and experiment. First, prosing a method for detecting the dry pressing voidage of mineral filler after camparing some different methods, using this method to detect mineral fillers with different dry pressing voidage powder, supplemented by the analysis of some powder properties.Such as specific surface area, hydrophilic coefficient, ethylene blue value and other performance indicators, combining the 70# asphalt and fillers with different dry pressing voidage, then getting the asphalt mortar of the powder binder ratio is 0.8, using dynamic shear rheometer(DSR) and bending beam rheometer (BBR) which belong the PG performance Grading Test to analyze the performance of asphalt mortar, studying the effect of dry pressing voidage on the high temperature performance, the low temperature performanc and the fatigue propertiese of asphalt mortar. Taking some tests on the the performance of mixture bases on the study of the asphalt mortar with different filler and different filler binder ratio. Using AC-20 mixture, determining the appropriate ratio at first, then taking mixture laboratory test, such as marshall test, water stability, high temperature stability and low temperature crack resistance, giving comparative study on the Marshall stability, flow value, immersion Marshall stability, freeze-thaw splitting strength ratio, dynamic stability, low temperature strength, maximum bending strain, low temperature splitting stiffness modulus of asphalt mixture with the powder with different dry pressing voidage. Finally, analysing the dry pressing voidage in different situations, combined with the actual situation and the scope of standards, putting forward the suitable dry pressing voidage which can be used in China, and putting forward some suggestions on the evaluation standard of mineral powder.