RAP掺量对厂拌热再生沥青混合料性能影响研究

Study on the Influence of RAP Content on the Performance of Plant Mix Hot Recycled Asphalt Mixture

为了进一步分析RAP掺量对混合料性能的影响规律,规范厂拌热再生沥青混合料RAP掺量范围,基于室内试验论文对再生剂的掺入方式及合理掺量、RAP掺量对混合料路用性能的影响规律进行研究。提出将再生剂添加到混合料再回收沥青的试验方案,该试验方法与实际工程应用更相符,研究表明相比于直接将再生剂添加到沥青中,该试验方案再生效果较差,建议应适当提高再生剂的掺量;添加再生剂能够显著提高老化沥青的针入度和延度,但软化点略有降低,确定本文再生剂掺量为8%;不同RAP掺量条件下混合料的体积指标差异不明显,但最佳沥青用量随RAP掺量的增加逐渐增大;随RAP掺量的增加,混合料高温稳定性先增大后减小,低温抗裂性和水稳定性逐渐降低,推荐厂拌热再生沥青混合料RAP掺量宜控制为30%。

In order to further analyze the influence law of RAP content on the performance of the mixture, standardize the scope of rap content of the plant mix hot recycled asphalt mixture, based on the laboratory test paper, the paper studies the influence law of the way and reasonable amount of the recycled agent, rap content on the road performance of the mixture. The experimental scheme of adding regenerant to the mixture to recycle asphalt is put forward, which is more consistent with the actual engineering application. The research shows that compared with adding regenerant directly to asphalt, the experimental scheme has poor regeneration effect. It is suggested that the amount of regenerant should be increased properly;adding regenerant can significantly improve the penetration and ductility of aging asphalt, but the softening point is slightly reduced with the increase of rap content, the high-temperature stability of the mixture increases first and then decreases, the low-temperature crack resistance and water stability decrease gradually. It is recommended that the RAP content should be controlled at 30%.