Based On Voids In Mineralaggregate(VMA) Of SMA Mixture Technology Research

In recent years, more and more SMA structure was used in the construction of highwayin Shaanxi province. However, how to select VMA value confused many road workers in theapplication process of the SMA pavement. Should we use the specification mechanically ormake appropriate adjustments to index requirement according to the actual situation of theproject. How much is the range of the adjustment? How is the SMA road performance afteradjusting? a series of problems make people at a loss. Therefore, it is very necessary to makea research on mixture technology of SMAbased on VMA.Firstly, this paper obtains the main factors that affect the value of VMA and the influencelaw of VMA on the road performance of SMA mixture through the analysis of the existingspecifications and related results. Secondly, studying the impact of various influencing factorson the VMA values and the regularity of raising and dropping of VMA changes withinfluencing factor. studying the variation of road performance of high and low temperaturestability and water stability of SMA mixture when VMA changes with the change of fibertype, asphalt aggregate ratio, specific absorption of aggregate and mixturegradation.Finally,putting forward the recommended minimum VMA value of various regionsin Shaanxi province through the concrete analysis of weather and traffic load of Shaanxiprovince. this paper derived the computational formula of VMA formed by the fourparameters of porosity VV, aggregate surface area SA, Synthetic gross volume relative densityof mineral aggregate rsband the thickness of asphalt film DA through the theoretical analysis,and calculating the recommended minimum VMA value of three regions in Shaanxi.Summing up the research results and ultimately raising the recommended minimum VMAvalue of various regions in Shaanxi province. the recommended minimum VMA valueobtained in this paper is feasible in northern Shaanxi through the SMA-13test road paved innorthern Shaanxi.