超高RAP掺量厂拌热再生沥青混合料研究及应用

Research and Application of Plant-mixed Hot Recycled Asphalt Mixture with Ultrahigh RAP Content

摘要:

为了推进回收沥青路面（reclaim asphalt pavement，RAP）材料的超高比率应用，通过室内试验研究提出了50%~80%RAP掺量下热再生混合料的材料组成比例，基于此开展了混合料的高温稳定性、低温抗裂性和水稳定性的研究。研究表明，热再生混合料的动稳定度与RAP掺量呈现同步增长的趋势，弯拉应变、残留稳定度和冻融劈裂强度比均与RAP掺量呈现负相关，RAP掺量在50%~80%时可确保热再生沥青混合料路面服役性能优异。基于实际热再生工程进行试验段应用，通过RAP变异性控制、减少沥青二次老化、加强新旧沥青融合等技术措施，有效实现了厂拌热再生技术中高效应用超高比例的RAP材料。

Abstract:

In order to promote the ultrahigh ratio application of reclaimed asphalt pavement (RAP) materials, the material composition ratio of hot recycled mixture with 50%~80% RAP content is proposed through the laboratory test research. Based on this, the high-temperature stability, low-temperature crack resistance and water stability of the mixture are studied. The research shows that the dynamic stability of the hot recycled mixture and the RAP content show a synchronous growth trend. The flexural tensile strain, residual stability and freeze-thaw splitting strength ratio are negatively correlated with the RAP content. When the RAP content is 50%~80%, the service performance of the hot recycled asphalt mixture pavement is excellent. Based on the actual thermal regeneration project, the application of the test section is carried out. Through the technical measures such as RAP variability control, reducing secondary aging of asphalt, and enhancing the integration of new and old asphalt, the efficient application of ultrahigh proportion RAP materials in the plant-mixed hot recycling technology has been effectively achieved.