基于强度特性的沥青混合料设计参数

为了改善沿海含盐高湿环境下沥青路面的水稳定性，首先，分析间接拉伸强度( ITS)用于沥青混合料沥青用量设计的可行性；然后，在不同条件下进行间接拉伸试验，分析温度、加载速率和沥青用量对ITS的影响；最后，对不同条件下混合料的ITS与冻融劈裂试验结果的相关性进行分析。研究结果表明：沥青混合料的ITS随试验温度的升高逐渐减小，随加载速率的增加逐渐增大，随沥青用量的增多先增大后减小，并在区间内某一用量下达到峰值；在温度40℃、加载速率5 mm/min的条件下，混合料的ITS与冻融劈裂强度比( TSR)的相关性最高，可以利用该条件下的ITS作为沿海地区混合料最佳沥青用量设计的力学参数。

Design Parameter of Asphalt Mixture Based on Strength Characteristic

To improve the water stability of asphalt pavement under the condition of salty and humid environment in coastal areas, the feasibility of applying indirect tensile strength to asphalt mixture design was analyzed first. Then, the indirect tensile tests under different conditions were carried out, and the influences of test temperature, loading rate and asphalt content on ITS were analyzed. Finally, the correlative analysis of ITS under different conditions and results of freeze-thaw splitting test was carried out. The results show that ITS of asphalt mixture decreases with the increasing of test temperature and increases with the increasing of loading rate. ITS increases with increasing of asphalt content at first and then decreases, and ITS gets its peak at certain asphalt content. Under the temperature of 40℃ and loading rate of 5mm/min, the correlation of ITS and TSR is the highest. The ITS under that condition can be regarded as a mechanical parameter for optimum asphalt content design of asphalt mixture in coastal areas.