击实次数对双层功能性沥青混合料稳定性的影响

在目前现有的单层沥青混合料及单层功能性沥青混合料的基础上,设计了一种上层OGFC沥青混合料与下层AC沥青混合料组合的双层沥青混合料,该种沥青混合料除了保留原有OGFC的功能特性外,又具有较好的力学性能。在针对双层沥青混合料马歇尔试件击实制作成型的基础上,考虑双层沥青混合料的强度与功能性等问题,研究采用不同击实次数组合(50×50、60×60、75×75、50×75、60×75)的击实形式,分别在25、60℃条件下对不同击实次数组合下的试件进行了马歇尔试验,以此来初步验证双层沥青混合料稳定性与击实次数组合之间的关系。同时研究基于数据拟合分析对不同击实次数组合下混合料的稳定性进行分析。研究表明:在不同击实次数组合下,双层功能性沥青混合料的密度、空隙率符合与击实次数的一般规律,试件的密度随着击实次数的增加逐渐增大,试件的空隙率随着击实次数的增加逐渐减小。此外,随着击实次数的增加双层功能性沥青混合料两层间层间连接逐渐密实、层间连接效果更好,所测得的稳定度随着击实次数的增加而逐渐增大。

Effect of compaction number on stability of two-layer functional asphalt mixture

Based on the existing single-layer asphalt mixture and single-layer functional asphalt mixture, this study designed a double-layer asphalt mixture with upper OGFC asphalt mixture and lower AC asphalt mixture. In addition to retaining the functional properties of the original OGFC, the asphalt mixture has good mechanical properties. On the basis of the compaction of the double-layer asphalt mixture Marshall test piece, considering the strength and functionality of the double-layer asphalt mixture, the Marshall test piece is studied in five kinds of different combinations of compaction times was made, The five compact combinations are 50×50, 60×60, 75×75, 50×75, 60×75. And the test pieces under different combinations of the number of times of compaction were tested by Marshall at 25 ° C and 60 ° C ,to verify the relationship between the stability of the layer asphalt mixture and the combination of the number of times of compaction. At the same time, based on the data fitting analysis, the stability of the mixture under different combinations of the number of times of compaction was analyzed. The research shows that under the combination of different times of compaction, the density and void ratio of the double-layer functional asphalt mixture meet the general rule of the number of times of compaction. The density of the test piece increases with the increase of the number of times of compaction. The void ratio gradually decreases as the number of times of compaction increases. In addition, with the increase of the number of times of compaction, the interlayer connection between the two layers of the functional asphalt mixture is gradually compacted and the interlayer connection effect is better, And as the number of compactions increases, the measured stability gradually increases.