The Viscoelasticity Experimental Analysis Of The Asphalt Mortar

Asphalt mixture consists of 3 parts, including coarse aggregate, fine aggregate and asphalt. We mix the fine aggregate into asphalt, which form a new mixture we named it asphalt mortar. Because the mixture is similar to the sand and the cement in cement concrete. As dispersed phase, the grain diameter of the fine aggregate below 4.75mm disperses in the asphalt matrix phase, which can form particles reinforced material. In this way we can see that mixing the fine aggregate may improve the property of asphalt mortar obviously. We use asphalt mortar instead of pure asphalt to fill into the space of coarse aggregate particles, which may improve pavement performance of asphalt concrete, especially the performance of asphalt mixture.Up to now, there are mainly two aspects to deal with how to improve the pavement performance of asphalt mixture. One is to study on the performance of asphalt mortar. The other is to study on the gradation of aggregate. However, both of them are ignored the study on the performance of asphalt mortar.This paper analyzes the effects caused by different fine aggregate contents and different aggregate particle diameters,. We find that the content and the diameter have influence on the basic performance of asphalt mortar through compressive strength tests, direct tensile tests and bending tests of small beam of asphalt mortar. Through the tests, we can see that with the increase of fine aggregate contents in asphalt mortar, all of the compression strength, tensile strength and bending strength increase. However, there will be a peak in the maximum flexure tensile strain, which illustrates that the content of aggregates is not bigger always better. There exists a optimum value. The diameter of the aggregate may have effect on the performance of asphalt mortar. That is, mixing the same weight aggregate, the aggregate with smaller diameter have greater effect on the performance of asphalt mortar than the one with larger diameter.We get viscoelastic parameters of asphalt mortar creeping by doing compression creep tests on asphalt mortar composed of different aggregates and using Burgers in creep curve fitting. The tests show that with the increase of the fine aggregate contests in asphalt mortar, the model parameters E1,E2,η1,η2 increase. And they have an exponential relationship with the fine aggregate contents. When we increase the contents of the fine aggregate in asphalt mortar, the instantaneous elasticity percentage of asphalt mortar increases progressively, the viscous flow percentage decreases progressively, the delayed elasticity percentage increases at first and then decreases and viscosity-elasticity rate decrease gradually. Namely, the asphalt mortar performs its elasticity increasingly.