【作者】 庞海峰；

【导师】 应荣华；

【作者基本信息】 长沙理工大学 ， 道路与铁道工程， 2009， 硕士

【摘要】 沥青混合料可看成是由粗集料（d>4.75 mm）、细集料（d<4.75 mm）和沥青3部分组成。将细集料加入沥青中,类似于水泥混凝土中的砂与水泥的混合物,因此称为沥青砂浆。作为分散相,颗粒粒径小于4.75 mm的细集料分散在沥青基体相中,形成颗粒增强材料,因而,细集料的加入可以明显改善沥青胶浆的性能。利用沥青砂浆替代纯沥青填充粗集料颗粒间的空隙,可以改善沥青混凝土的路用性能,特别是可进一步提高沥青混合料的路用性能。目前,对于如何提高沥青混合料路用性能的研究主要从两方面入手,即沥青胶浆性能研究和集料级配研究,而忽略了对沥青砂浆性能研究。论文通过沥青砂浆的抗压强度、直接拉伸和小梁弯曲试验,分析了不同细集料含量、不同粒径的集料对沥青砂浆基本性能的影响。通过试验分析发现,随着沥青砂浆中细集料含量增加,其抗压强度、拉伸强度和弯曲强度均随之增加,但最大弯拉应变却会出现一个峰值,说明并不是砂浆中集料含量越大越好,其存在一个最佳值;集料组成的粗细也会影响到沥青砂浆的性能,加入相同质量的集料,粒径小的集料比粒径大的集料对沥青砂浆性能的影响要大。对不同集料组成的沥青砂浆进行单轴压缩蠕变试验,并采用Burgers模型对蠕变曲线进行拟合,得到沥青砂浆蠕变的粘弹性参数。通过试验分析发现,随着沥青砂浆中细集料含量的增加,Burgers模型参数E₁、E₂、η₁、η₂均随之增加,且与细集料含量成指数关系;随着沥青砂浆中细集料含量的增加,沥青砂浆的瞬时弹性百分比递增,粘性流动百分比递减,而延迟弹性百分比先增后减,粘弹比逐渐减小,即沥青砂浆越来越表现为弹性。更多还原

【Abstract】 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.更多还原