Rutting of asphalt pavement occurs earlier and is more serious under the increasingly heavy traffic load conditions that can be found in subtropical monsoon climate regions.High modulus asphalt concrete(HMAC)with exce...Rutting of asphalt pavement occurs earlier and is more serious under the increasingly heavy traffic load conditions that can be found in subtropical monsoon climate regions.High modulus asphalt concrete(HMAC)with excellent anti-rutting and anti-fatigue properties is generally used to mitigate this issue.Given the relatively high cost of the additives used in this type of asphalt,in this study the feasibility of using recycled asphalt mixture(RAP)and Trinidad lake asphalt(TLA)for the preparation of HMAC is considered.The mineral composition of the RAP is first analyzed,then the TLA modified asphalt with different levels of RAP content is used to assess the effect of RAP on the performance of the mixture.Finally,the high-temperature rheological properties of extracted bitumen and the adhesion characteristic between mineral and bitumen are analyzed.The results show that after RAP combustion,the yellowish and greyish minerals display different alkalinity values,while the greyish mineral exhibits an improved ability to combine with bitumen.Thus,RAP can significantly enhance the high-temperature rutting resistance of TLA modified asphalt mixtures.The aged bitumen in RAP makes the mixed binder harder and improves its rheological properties at high temperatures.展开更多
【目的】针对不同特立尼达湖沥青(Trinidad Lake Asphalt,TLA)掺量的苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrene-butadiene-styrene,SBS)复合改性沥青,通过建立宏观和微观性能技术指标体系揭示TLA和SBS提升复合改性沥青性能的作用机理,为...【目的】针对不同特立尼达湖沥青(Trinidad Lake Asphalt,TLA)掺量的苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrene-butadiene-styrene,SBS)复合改性沥青,通过建立宏观和微观性能技术指标体系揭示TLA和SBS提升复合改性沥青性能的作用机理,为沥青路面材料的优化提供理论支撑。【方法】采用试验分析方法,设计了13组不同质量配比的TLA/SBS复合改性沥青试验。通过对复合改性沥青的软化点、针入度、延度等性能指标进行测试并结合微观结构表征,揭示不同的TLA掺量对复合改性沥青性能的影响机理。【结果】TLA掺量的增加能显著地提升复合改性沥青在高温下的稳定性,TLA掺量每增加1%,软化点就提高0.221℃,并且TLA掺量的增加能降低复合改性沥青对温度的敏感性;TLA中的灰分均匀分布形成的粗糙表面与孔隙协同作用,增强了基体的稳定性;根据AC-10型沥青混合料的施工要求,确定TLA和SBS最佳质量比为3∶7;微观分析表明,火山灰质灰分的叠加可增强沥青界面之间的结合,SiO_(2)基矿物的组成及其独特的粒度分布可显著地改善复合改性沥青胶浆的黏韧性,通过调控灰分的分布可显著地改善复合改性沥青的性能。【结论】研究结果可为湿热地区重载交通条件下沥青路面的材料设计与性能提升提供方法和依据。展开更多
基金This work was funded by the Self-Financing Technology Plan Project of Foshan(2020001005386)Open Fund of Key Laboratory of Geological Survey and Evaluation of Ministry of Education(No.GLAB2019ZR01).
文摘Rutting of asphalt pavement occurs earlier and is more serious under the increasingly heavy traffic load conditions that can be found in subtropical monsoon climate regions.High modulus asphalt concrete(HMAC)with excellent anti-rutting and anti-fatigue properties is generally used to mitigate this issue.Given the relatively high cost of the additives used in this type of asphalt,in this study the feasibility of using recycled asphalt mixture(RAP)and Trinidad lake asphalt(TLA)for the preparation of HMAC is considered.The mineral composition of the RAP is first analyzed,then the TLA modified asphalt with different levels of RAP content is used to assess the effect of RAP on the performance of the mixture.Finally,the high-temperature rheological properties of extracted bitumen and the adhesion characteristic between mineral and bitumen are analyzed.The results show that after RAP combustion,the yellowish and greyish minerals display different alkalinity values,while the greyish mineral exhibits an improved ability to combine with bitumen.Thus,RAP can significantly enhance the high-temperature rutting resistance of TLA modified asphalt mixtures.The aged bitumen in RAP makes the mixed binder harder and improves its rheological properties at high temperatures.
文摘【目的】针对不同特立尼达湖沥青(Trinidad Lake Asphalt,TLA)掺量的苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrene-butadiene-styrene,SBS)复合改性沥青,通过建立宏观和微观性能技术指标体系揭示TLA和SBS提升复合改性沥青性能的作用机理,为沥青路面材料的优化提供理论支撑。【方法】采用试验分析方法,设计了13组不同质量配比的TLA/SBS复合改性沥青试验。通过对复合改性沥青的软化点、针入度、延度等性能指标进行测试并结合微观结构表征,揭示不同的TLA掺量对复合改性沥青性能的影响机理。【结果】TLA掺量的增加能显著地提升复合改性沥青在高温下的稳定性,TLA掺量每增加1%,软化点就提高0.221℃,并且TLA掺量的增加能降低复合改性沥青对温度的敏感性;TLA中的灰分均匀分布形成的粗糙表面与孔隙协同作用,增强了基体的稳定性;根据AC-10型沥青混合料的施工要求,确定TLA和SBS最佳质量比为3∶7;微观分析表明,火山灰质灰分的叠加可增强沥青界面之间的结合,SiO_(2)基矿物的组成及其独特的粒度分布可显著地改善复合改性沥青胶浆的黏韧性,通过调控灰分的分布可显著地改善复合改性沥青的性能。【结论】研究结果可为湿热地区重载交通条件下沥青路面的材料设计与性能提升提供方法和依据。
