高性能RAP料配合比设计

Mixture Proportion Design of High-Performance RAP Materials

对比分析了振动压实和重型击实成型方式下,级配RAP料物理、力学特性,研究表明使用振动压实的方法更能够代表实际的压实效果。采用粒子干涉理论对粗集料级配进行了优化,采用最大密度曲线理论Ⅰ法对细集料进行了优化,通过变化粗细集料比例,以最大干密度与强度双优化指标优选级配,初步提出具有优良物理力学特性的级配。在此基础上,进一步深入研究筛孔通过率对级配RAP料力学性能的影响规律,并以力学性能最优为原则,提出了基于振动成型的级配RAP料骨架密实级配。以劈裂强度为指标,提出了以长度为2.5 cm,掺量为1‰的仿钢纤维(PPTF)作为高性能RAP料的增强纤维。

Firstly,the physical and mechanical properties of gradation RAP material were compared and analyzed in the vibration compaction and heavy hammer compaction tests;and the method of vibration compaction was ensured to be more representative for the actual compaction effect.Secondly,the particle interference theory was used to optimize the coarse aggregate gradation and the maximum density curve theory I method was used to optimize the fine aggregate gradation.Thirdly,the gradations with excellent physical and mechanical properties were proposed preliminarily by changing the ratio of coarse aggregate and fine aggregate and optimizing the gradation with double optimization index,that is the maximum dry density and strength.On the above basis,the regularity for the influence of the sieve pore passing rate on the mechanical properties of gradation RAP material was further researched.Fourthly,according to the principle of the optimal mechanical properties,the skeleton dense gradation of gradation RAP material was put forward on the base of the vibration molding.Finally,taking the split strength as index,the imitated steel fiber （PPTF） with the length of 2.5 cm and the content of 1 ‰ was proposed to be the reinforcement fiber of high-performance RAP material.