掺加硅藻土的温拌再生混合料路用性能及改性机理分析

摘要

针对温拌再生混合料低温抗裂性差、水稳定性不足等技术缺陷，提出采用硅藻土改性温拌再生混合料方案，研究硅藻土掺量对温拌再生混合料的体积特性和力学指标的影响，进而基于车辙试验、小梁弯曲试验、冻融循环试验和疲劳试验研究了不同硅藻土掺量下温拌再生混合料的综合路用性能，并揭示了硅藻土对温拌再生混合料的改性机理。结果表明：随着硅藻土掺量的增大，温拌再生混合料的最佳油石比增大，掺加硅藻土可显著提高温拌再生混合料的低温抗裂性以及水稳定性，11％硅藻土掺量下温拌再生混合料的抗疲劳性能最优，硅藻土对温拌再生混合料的改性机理在于其提高了再生混合料的沥青膜厚、提高了沥青胶浆与集料之间的粘附性、弥补了老化沥青与新沥青结合的界面缺陷。%In order to improve the low temperature cracking,water stability and other technical defects of warm﹣recycled asphalt mixture,this article proposed use of diatomite modified warm mix recy﹣cled mixtures plan,Research diatomite Recycled content on Warm Mix mixture volume characteristics and mechanical indicators,and then based on the rutting test,beam bending test,freeze﹣thaw cycle test and fatigue test systems studied the road performance of warm﹣recycled asphalt mixture under different dosage diatomite ,and reveals the mechanism of diatomite on warm﹣recycled asphalt mixture.The results show that:with the increasing content of diatomaceous,warm recycled asphalt mixture optimum ratio increa﹣ses,Adding diatomite can significantly improve the low temperature cracking resistanceand water stability of warm﹣recycled asphalt mixture,under 1 1 % diatomite dosage warm mix recycled mixture fatigue optimal performance,the Mechanism of diatomite is Increased asphalt film thickness,increase the adhesion be﹣tween asphalt rubber paste and aggregate,and makes up for the aging of asphalt combined with new as﹣phalt interface defects of warm﹣recycled asphalt mixture.