基于DMA方法的玻璃态转变温度与沥青混合料低温性能研究

Study on Glass Transition Temperature and Low Temperature Performance of Asphalt Mixture Based on Dynamic Mechanical Analysis Method

为进一步探究沥青与沥青混合料玻璃态转变温度与沥青混合料低温性能的相关性,以交通运输部公路科学研究院足尺环道(RIOHTrack)为依托,采用动态力学分析仪在弯拉受力模式下用沥青和沥青混合料试件进行温度扫描试验,通过函数拟合确定材料的玻璃态转变温度,进而比较不同定义方式下材料的玻璃态转变温度的变化趋势,探究沥青与沥青混合料相态转变温度的相关性。最后通过与低温弯曲小梁试验的实验结果的相关性和灰关联度分析,讨论利用沥青与沥青混合料的玻璃态转变温度评价沥青混合料低温性能的可行性。结果表明:(1)对于同一种材料,不同的玻璃态转变温度定义下获得的玻璃态转变温度之间存在良好的相关性;(2)在相同级配和相同试验条件下,沥青是影响沥青混合料玻璃态转变温度的主要因素;(3)在弯拉受力模式下沥青与沥青混合料的玻璃态转变温度与材料的低温性能相关性良好,但通过灰关联度分析发现采用沥青混合料的玻璃态转变温度评价混合料的低温性能更加合理。

In order to further explore the relationship between the glass transition temperature and the low temperature performance of the mixture,this research is based on RIOHTrack,the dynamic mechanical analyzer was utilized to scan the asphalt and asphalt mixture under the flexural tensile loading model.And then the glass transition temperature of material was obtained through function fitting.On the basis of this,the trends of the glass transition temperature obtained by different definitions is compared,and the correlation between glass transition temperature of asphalt and asphalt mixture is discussed.Finally,this paper investigates the correlation analysis and gray correlation analysis to discuss the feasibility of evaluating the low temperature performance of asphalt mixture by glass transition temperature.The test result indicates that,(1)for the same material,there is a good correlation between the glass transition temperatures obtained by different glass transition temperatures definition;(2)asphalt is the main factor affecting the glass transition temperature of asphalt mixture under the same gradation and the same experimental condition;(3)there is a good correlation between the glass transition temperature and low temperature performance under flexural tensile loading model,it is more reasonable to evaluate the low-temperature performance of asphalt mixture by the glass transition temperature of asphalt mixture through the gray correlation analysis.