基于多应力蠕变恢复试验的醋酸纤维改性沥青蠕变特性研究

Study on Creep Characteristics of Cellulose Acetate Modified Asphalt Binder Based on Multi-stress Creep Recovery Test

为了研究掺加不同来源醋酸纤维改性沥青的蠕变特性,选择4组醋酸纤维掺量制备醋酸纤维改性沥青,测试两种醋酸纤维改性沥青的针入度和软化点,并利用动态剪切流变仪进行多应力蠕变恢复试验,测试50℃时0.1kPa和3.2kPa两种应力水平的剪切应变,对比分析两种醋酸纤维不同掺量改性沥青的恢复率和不可恢复柔量。结果表明:随着醋酸纤维掺量的增加,改性沥青的针入度减小,软化点增大;掺加回收醋酸纤维改性沥青其剪切应变大于掺加原始醋酸纤维的剪切应变;掺加原始醋酸纤维改性沥青的恢复率均大于掺加回收醋酸纤维改性沥青,而不可恢复柔量的变化规律则相反。

In order to study the creep characteristics of the cellulose acetate modified asphalt binder from different sources,four groups of cellulose acetates were selected to prepare the cellulose acetate modified asphalt binders.The penetrations and softening points of two kinds of modified asphalt binders were measured.The multiple stress creep recovery test was carried out with the dynamic shear rheometer,andtheir shear strains were tested under 0.1 kPa and 3.2 kPa at 50 ° C.In addition,the recovery rates and irrecoverable complianceswere analyzed for the two types of cellulose acetate modified asphalt binder withdifferentdosages.The results show that the penetration of modified asphalt decreases and the softening point increases with the increase of cellulose acetate content;the shear strain of the recycled cellulose acetate modified asphalt binder is greater than that of the original cellulose acetate modified asphalt binder.The recovery rate of the original cellulose acetate modified asphalt binder is higher than that of the recycled cellulose acetate modified asphalt binder,and the change law of the irrecoverable compliance is opposite.