基于间接拉伸试验模式的沥青混合料动态模量研究

鉴于间接拉伸模式决定沥青混合料动态模量的重要意义，基于间接拉伸试验模式，采用目前我国常用的2种沥青混合料，发展沥青混合料间接拉伸试验动态模量的测定和分析方法。基于GPM测试模式，通过修正参数，修正二维平面应力假设和试件膨胀的影响，根据修正的应力和应变决定沥青混合料的间接拉伸动态模量。根据时-温转换原则，基于Hirsch模型估算混合料模量极大值，分别采用Global Aging模型和Arrhenius模型获得移位因子，通过数值优化建立了参考温度为20℃的2种常用沥青混合料动态模量主曲，得出了主曲线的Sigmoidal数学模型。根据对2种混合料的动态模量主曲线比较分析表明AC-20型沥青混合料对加载频率和对温度的依赖性都较低于AC-13C型混合料，尤其在低频段表现更为明显。

Study on Dynamic Modulus of HMA Based on Indirect Tension Test Mode

Recognizing the importance of the indirect tension dynamic modulus for the asphalt pavement, Based on the indirect tension test mode, adopting two kinds of asphalt mixes in China, the measurement and analysis of dynamic modulus in indirect tension mode were developed. Based on the GPM testing mode, the correction factors was used to take into account the effect of the limitation of the biaxial plane stress assumption and specimen surface bulging, the indirect tension dynamic modulus were determined in the light of the corrected strain and stress. Master curves are constructed using the principle of time-temperature superposition. The Hirsch model was used to estimate the limiting maximum modulus of the mixtures, the Global Aging Model and the Arrhenius Model are used to obtain the shrift factors, the master curves and the Sigmodial function of master curves are determined by numerical optimization for two mixes. According to the comparison of indirect tension dynamic modulus for two mixes indicate: the frequency and temperature dependence of AC-20 is lower than AC-13C, especially in low-frequency.