Abstract: Three groups of AC-13C asphalt mixtures were designed according to different iron tailings content. Through the high and low temperature performance test and soaking Hamburg rutting test, it is shown that the high and low temperature performance of iron tailings asphalt mixture is good, and the water stability is lower than that of the reference group on the premise of meeting the requirements. The dynamic modulus and phase angle of three groups of mixture was tested by asphalt mixture performance tester (AMPT Pro). The test results show that with the increase of loading frequency, the increase of dynamic modulus of iron tailings asphalt mixture is smaller than that of ordinary mixture; the phase angle decreases with the increase of loading frequency at low and normal temperature, and increases with the increase of loading frequency when the temperature is higher than 35 ℃. According to the principle of time-temperature equivalence, the main dynamic modulus curve at the reference temperature of 20 ℃ is obtained by nonlinear least squares fitting. The dynamic modulus at any frequency can be found through the main curve, and the dynamic response characteristics of the iron tailings asphalt mixture can be further obtained.

Key words: highway engineering, iron tailings, dynamic modulus, phase angle, time-temperature equivalence principle, least squares method

摘要： 根据不同铁尾矿掺量设计了3组AC-13C型沥青混合料，高低温性能试验和浸水汉堡车辙试验表明：铁尾矿沥青混合料高低温性能良好，水稳定性在满足要求的前提下相较于基准组有所降低。采用沥青混合料性能试验机(AMPT Pro)测试了3组混合料的动态模量和相位角，试验结果表明：掺加铁尾矿的沥青混合料随加载频率增大，其动态模量增幅小于普通混合料；相位角在低温和常温下随加载频率的增大而减小，当温度高于35 ℃时，随加载频率的增大而增大。根据时间-温度等效原理，采用非线性最小二乘法拟合得到参考温度20 ℃下的动态模量主曲线，通过主曲线可以查找任意频率下的动态模量，进一步获得铁尾矿沥青混合料的动态响应特性。

关键词: 道路工程, 铁尾矿, 动态模量, 相位角, 时温等效原理, 最小二乘法