In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road perfor...In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road performance of emulsified asphalt cold recycled mixtures(ECRM),this study employed recycled asphalt pavement(RAP)and reclaimed inorganic binder stabilized aggregate(RAI)as dual recycled materials for ECRM preparation.The blending ratios of reclaimed base and surface layer mixtures significantly influence ECRM's performance,with adjusted proportions substantially improving compressive strength and dynamic modulus.Firstly,three distinct proportioning options were developed for the recycled materials.Mix designs incorporating varying RAP/RAI ratios were used to determine the optimal mix parameters:moisture content,cement dosage,and emulsified asphalt content.Subsequently,comprehensive performance evaluations were conducted through high-temperature wheel tracking tests,freeze-thaw splitting tests,uniaxial compression tests,and dynamic modulus measurements to analyze the pavement characteristics of the three ECRM formulations.Experimental results demonstrate:Compared with ECRM with a blending ratio of RAP:RAI:new aggregate=30:50:20(Option 1),the dynamic stability,freeze-thaw splitting strength ratio,compressive strength,and compressive resilient modulus of ECRM under Option 3(RAP:RAI:new aggregate=50:30:20)decreased by 31.8%,5.2%,16.4%,and 13.1%,respectively.This indicates that increasing RAP content while reducing RAI proportion enhances the tensile strength of ECRM,yet adversely affects its high-temperature stability,moisture resistance,and compressive performance.This work not only addresses the challenge of jointly utilizing asphalt pavement waste and base waste,but also provides a cost-effective and sustainable method for the stable application of milling material resources in road engineering.展开更多
Sets of cold-filled SMA-13 asphalt mixture were designed by means of orthogonal design method. The bending and low temperature creep tests of the cold-filled SMA-13 asphalt mixture were carried out. The related models...Sets of cold-filled SMA-13 asphalt mixture were designed by means of orthogonal design method. The bending and low temperature creep tests of the cold-filled SMA-13 asphalt mixture were carried out. The related models of the fractal dimension and the road performance evaluation index including low temperature bending failure strain εB and bending strength RB are established by using fractal theory. The model can be used to predict the low temperature performance of cold-filled SMA-13 asphalt mixture according to the design gradation, which can reduce the test workload and improve the working efficiency, so as to provide the reference for engineering design.展开更多
为研究激活作用下乳化沥青冷再生混合料强度的增强机理,首先研究激活作用下乳化沥青冷再生混合料路用性能的演变,继而通过扫描电子显微镜(scanning electron microscopy,SEM)、能量色散谱仪(energy dispersive spectroscopy,EDS)和原子...为研究激活作用下乳化沥青冷再生混合料强度的增强机理,首先研究激活作用下乳化沥青冷再生混合料路用性能的演变,继而通过扫描电子显微镜(scanning electron microscopy,SEM)、能量色散谱仪(energy dispersive spectroscopy,EDS)和原子力显微镜(atomic force microscopy,AFM)研究激活作用下界面过渡区(interfacial transition zone,ITZ)的形貌变化,分析混合料强度与界面过渡区形貌间的关系。结果表明:在乳化沥青冷再生混合料中加入激活剂能够有效提高其高温性能、低温性能和水稳定性能,激活乳化沥青冷再生混合料的15℃劈裂强度较不掺加激活剂的乳化沥青冷再生混合料提高达30.8%;激活乳化沥青冷再生混合料的界面结构紧密,随着养生时间的增加,界面过渡区宽度逐渐减小。激活作用下养生7 d的界面过渡区宽度与未激活状态下相比减小了77.8%。激活作用下旧沥青中的轻质组分可以得到有效补充,同时,激活剂中的苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrence-butadiene-styrence,SBS)可以扩散到旧沥青中进行改性,从而促进了新旧沥青的融合。展开更多
基金sponsored by National Natural Science Foundation of China(No.52308466)SASAC Science and Technology Innovation Project(JF-23-01-0063)Shaanxi Provincial Transportation Research Project(25-84 K,25-85 K).
文摘In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road performance of emulsified asphalt cold recycled mixtures(ECRM),this study employed recycled asphalt pavement(RAP)and reclaimed inorganic binder stabilized aggregate(RAI)as dual recycled materials for ECRM preparation.The blending ratios of reclaimed base and surface layer mixtures significantly influence ECRM's performance,with adjusted proportions substantially improving compressive strength and dynamic modulus.Firstly,three distinct proportioning options were developed for the recycled materials.Mix designs incorporating varying RAP/RAI ratios were used to determine the optimal mix parameters:moisture content,cement dosage,and emulsified asphalt content.Subsequently,comprehensive performance evaluations were conducted through high-temperature wheel tracking tests,freeze-thaw splitting tests,uniaxial compression tests,and dynamic modulus measurements to analyze the pavement characteristics of the three ECRM formulations.Experimental results demonstrate:Compared with ECRM with a blending ratio of RAP:RAI:new aggregate=30:50:20(Option 1),the dynamic stability,freeze-thaw splitting strength ratio,compressive strength,and compressive resilient modulus of ECRM under Option 3(RAP:RAI:new aggregate=50:30:20)decreased by 31.8%,5.2%,16.4%,and 13.1%,respectively.This indicates that increasing RAP content while reducing RAI proportion enhances the tensile strength of ECRM,yet adversely affects its high-temperature stability,moisture resistance,and compressive performance.This work not only addresses the challenge of jointly utilizing asphalt pavement waste and base waste,but also provides a cost-effective and sustainable method for the stable application of milling material resources in road engineering.
文摘Sets of cold-filled SMA-13 asphalt mixture were designed by means of orthogonal design method. The bending and low temperature creep tests of the cold-filled SMA-13 asphalt mixture were carried out. The related models of the fractal dimension and the road performance evaluation index including low temperature bending failure strain εB and bending strength RB are established by using fractal theory. The model can be used to predict the low temperature performance of cold-filled SMA-13 asphalt mixture according to the design gradation, which can reduce the test workload and improve the working efficiency, so as to provide the reference for engineering design.
文摘为研究激活作用下乳化沥青冷再生混合料强度的增强机理,首先研究激活作用下乳化沥青冷再生混合料路用性能的演变,继而通过扫描电子显微镜(scanning electron microscopy,SEM)、能量色散谱仪(energy dispersive spectroscopy,EDS)和原子力显微镜(atomic force microscopy,AFM)研究激活作用下界面过渡区(interfacial transition zone,ITZ)的形貌变化,分析混合料强度与界面过渡区形貌间的关系。结果表明:在乳化沥青冷再生混合料中加入激活剂能够有效提高其高温性能、低温性能和水稳定性能,激活乳化沥青冷再生混合料的15℃劈裂强度较不掺加激活剂的乳化沥青冷再生混合料提高达30.8%;激活乳化沥青冷再生混合料的界面结构紧密,随着养生时间的增加,界面过渡区宽度逐渐减小。激活作用下养生7 d的界面过渡区宽度与未激活状态下相比减小了77.8%。激活作用下旧沥青中的轻质组分可以得到有效补充,同时,激活剂中的苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrence-butadiene-styrence,SBS)可以扩散到旧沥青中进行改性,从而促进了新旧沥青的融合。
