高原寒冷地区沥青混合料劈裂强度影响因素

Influencing Factors on Splitting Strength of Asphalt Mixture in Plateau Cold Region

针对青藏高原地区的气候特点,试验分析了油石比、温度、加载速率等对沥青混合料劈裂强度的影响。结果表明,不同温度条件下,油石比对沥青混合料劈裂强度的影响有所不同。高温时,沥青混合料劈裂强度随油石比的增大而波动变化,但影响较小;常温时,劈裂强度随油石比的增大呈抛物线形变化,出现峰值;低温时,劈裂强度随油石比的增大呈增大趋势。在相同的加载速率下,劈裂强度随温度的升高而减小。在常温及高温条件下,劈裂强度最大值及其对应的油石比均随温度的升高而减小。-10℃时的劈裂强度对加载速度的变化比较敏感。

According to the climate feature of the Qinghai-Tibet plateau area,influences of asphalt-aggregate ratio,temperature and loading rate on the splitting strength of asphalt mixture are tested and analyzed.The results show that effects of asphalt-aggregate ratio on the splitting strength under different temperature are varying.With the asphalt-aggregate ratio increasing,the splitting strength fluctuation change at high temperature,and parabola change at normal temperature,and increase at low temperature.Under the same loading rate,the splitting strength decrease with the temperature increasing.Under the high and normal temperature,the maximum splitting strength and the corresponding optimal asphalt-aggregate ratio all decrease with the temperature increasing.The splitting strength of-10℃is sensitive to changing of the loading rate.